fully implement and deploy explicit x-thread signal connection syntax (testing comes next)

git-svn-id: svn://localhost/ardour2/branches/3.0@6379 d708f5d6-7413-0410-9779-e7cbd77b26cf

86 files changed, 336 insertions, 295 deletions

diff --git a/gtk2_ardour/ardour_ui.cc b/gtk2_ardour/ardour_ui.cc
index 7deeae7bf7..23df74e6fd 100644
--- a/gtk2_ardour/ardour_ui.cc
+++ b/gtk2_ardour/ardour_ui.cc
@@ -234,20 +234,20 @@ ARDOUR_UI::ARDOUR_UI (int *argcp, char **argvp[])
 
 	last_shuttle_request = last_peak_grab = 0; //  get_microseconds();
 
-	ARDOUR::Diskstream::DiskOverrun.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::disk_overrun_handler));
-	ARDOUR::Diskstream::DiskUnderrun.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::disk_underrun_handler));
+	ARDOUR::Diskstream::DiskOverrun.connect (forever_connections, boost::bind (&ARDOUR_UI::disk_overrun_handler, this), gui_context());
+	ARDOUR::Diskstream::DiskUnderrun.connect (forever_connections, boost::bind (&ARDOUR_UI::disk_underrun_handler, this), gui_context());
 
 	/* handle dialog requests */
 
-	ARDOUR::Session::Dialog.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::session_dialog));
+	ARDOUR::Session::Dialog.connect (forever_connections, ui_bind (&ARDOUR_UI::session_dialog, this, _1), gui_context());
 
-	/* handle pending state with a dialog */
+	/* handle pending state with a dialog (PROBLEM: needs to return a value and thus cannot be x-thread) */
 
-	ARDOUR::Session::AskAboutPendingState.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::pending_state_dialog));
+	ARDOUR::Session::AskAboutPendingState.connect_same_thread (forever_connections, boost::bind (&ARDOUR_UI::pending_state_dialog, this));
 
-	/* handle sr mismatch with a dialog */
+	/* handle sr mismatch with a dialog (PROBLEM: needs to return a value and thus cannot be x-thread) */
 
-	ARDOUR::Session::AskAboutSampleRateMismatch.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::sr_mismatch_dialog));
+	ARDOUR::Session::AskAboutSampleRateMismatch.connect_same_thread (forever_connections, boost::bind (&ARDOUR_UI::sr_mismatch_dialog, this, _1, _2));
 
 	/* lets get this party started */
 
@@ -329,10 +329,10 @@ ARDOUR_UI::create_engine ()
 		return -1;
 	}
 
-	engine->Stopped.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::engine_stopped));
-	engine->Running.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::engine_running));
-	engine->Halted.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::engine_halted));
-	engine->SampleRateChanged.connect (forever_connections, sigc::mem_fun(*this, &ARDOUR_UI::update_sample_rate));
+	engine->Stopped.connect (forever_connections, boost::bind (&ARDOUR_UI::engine_stopped, this), gui_context());
+	engine->Running.connect (forever_connections, boost::bind (&ARDOUR_UI::engine_running, this), gui_context());
+	engine->Halted.connect (forever_connections, boost::bind (&ARDOUR_UI::engine_halted, this), gui_context());
+	engine->SampleRateChanged.connect (forever_connections, ui_bind (&ARDOUR_UI::update_sample_rate, this, _1), gui_context());
 
 	post_engine ();
 
@@ -407,7 +407,7 @@ ARDOUR_UI::post_engine ()
 	update_cpu_load ();
 	update_sample_rate (engine->frame_rate());
 
-	Config->ParameterChanged.connect (forever_connections, sigc::mem_fun (*this, &ARDOUR_UI::parameter_changed));
+	Config->ParameterChanged.connect (forever_connections, ui_bind (&ARDOUR_UI::parameter_changed, this, _1), gui_context());
 	boost::function<void (string)> pc (boost::bind (&ARDOUR_UI::parameter_changed, this, _1));
 	Config->map_parameters (pc);
 
diff --git a/gtk2_ardour/ardour_ui_dialogs.cc b/gtk2_ardour/ardour_ui_dialogs.cc
index 7cbf0df3e2..a15d8fc2be 100644
--- a/gtk2_ardour/ardour_ui_dialogs.cc
+++ b/gtk2_ardour/ardour_ui_dialogs.cc
@@ -37,6 +37,7 @@
 #include "theme_manager.h"
 #include "bundle_manager.h"
 #include "keyeditor.h"
+#include "gui_thread.h"
 
 #include "i18n.h"
 
@@ -113,14 +114,15 @@ ARDOUR_UI::set_session (Session *s)
 	Blink.connect (sigc::mem_fun(*this, &ARDOUR_UI::sync_blink));
 	Blink.connect (sigc::mem_fun(*this, &ARDOUR_UI::audition_blink));
 
-	_session->Xrun.connect (_session_connections, sigc::mem_fun(*this, &ARDOUR_UI::xrun_handler));
-	_session->RecordStateChanged.connect (_session_connections, sigc::mem_fun (*this, &ARDOUR_UI::record_state_changed));
-	_session->locations()->added.connect (_session_connections, sigc::mem_fun (*this, &ARDOUR_UI::handle_locations_change));
-	_session->locations()->removed.connect (_session_connections, sigc::mem_fun (*this, &ARDOUR_UI::handle_locations_change));
-	_session->TransportStateChange.connect (_session_connections, sigc::mem_fun(*this, &ARDOUR_UI::map_transport_state));
-	_session->AuditionActive.connect (_session_connections, sigc::mem_fun(*this, &ARDOUR_UI::auditioning_changed));
-	_session->SoloActive.connect (_session_connections, sigc::mem_fun(*this, &ARDOUR_UI::soloing_changed));
-	_session->DirtyChanged.connect (_session_connections, sigc::mem_fun(*this, &ARDOUR_UI::update_autosave));
+	_session->RecordStateChanged.connect (_session_connections, boost::bind (&ARDOUR_UI::record_state_changed, this), gui_context());
+	_session->TransportStateChange.connect (_session_connections, boost::bind (&ARDOUR_UI::map_transport_state, this), gui_context());
+	_session->DirtyChanged.connect (_session_connections, boost::bind (&ARDOUR_UI::update_autosave, this), gui_context());
+
+	_session->Xrun.connect (_session_connections, ui_bind (&ARDOUR_UI::xrun_handler, this, _1), gui_context());
+	_session->SoloActive.connect (_session_connections, ui_bind (&ARDOUR_UI::soloing_changed, this, _1), gui_context());
+	_session->AuditionActive.connect (_session_connections, ui_bind (&ARDOUR_UI::auditioning_changed, this, _1), gui_context());
+	_session->locations()->added.connect (_session_connections, ui_bind (&ARDOUR_UI::handle_locations_change, this, _1), gui_context());
+	_session->locations()->removed.connect (_session_connections, ui_bind (&ARDOUR_UI::handle_locations_change, this, _1), gui_context());
 
 	/* Clocks are on by default after we are connected to a session, so show that here.
 	*/
diff --git a/gtk2_ardour/ardour_ui_options.cc b/gtk2_ardour/ardour_ui_options.cc
index f917fd429d..acd49fb2a9 100644
--- a/gtk2_ardour/ardour_ui_options.cc
+++ b/gtk2_ardour/ardour_ui_options.cc
@@ -270,7 +270,7 @@ ARDOUR_UI::toggle_editing_space()
 void
 ARDOUR_UI::setup_session_options ()
 {
-	_session->config.ParameterChanged.connect (_session_connections, sigc::mem_fun (*this, &ARDOUR_UI::parameter_changed));
+	_session->config.ParameterChanged.connect (_session_connections, ui_bind (&ARDOUR_UI::parameter_changed, this, _1), gui_context());
 	boost::function<void (std::string)> pc (boost::bind (&ARDOUR_UI::parameter_changed, this, _1));
 	_session->config.map_parameters (pc);
 }
diff --git a/gtk2_ardour/audio_clock.cc b/gtk2_ardour/audio_clock.cc
index 0847031df4..86497709c6 100644
--- a/gtk2_ardour/audio_clock.cc
+++ b/gtk2_ardour/audio_clock.cc
@@ -35,6 +35,7 @@
 #include "audio_clock.h"
 #include "utils.h"
 #include "keyboard.h"
+#include "gui_thread.h"
 #include "i18n.h"
 
 using namespace ARDOUR;
@@ -214,7 +215,7 @@ AudioClock::AudioClock (std::string clock_name, bool transient, std::string widg
 	clock_base.add_events (Gdk::BUTTON_PRESS_MASK|Gdk::BUTTON_RELEASE_MASK|Gdk::SCROLL_MASK);
 	clock_base.signal_button_release_event().connect (sigc::bind (sigc::mem_fun (*this, &AudioClock::field_button_release_event), Timecode_Hours));
 
-	Session::TimecodeOffsetChanged.connect (_session_connections, sigc::mem_fun (*this, &AudioClock::timecode_offset_changed));
+	Session::TimecodeOffsetChanged.connect (_session_connections, boost::bind (&AudioClock::timecode_offset_changed, this), gui_context());
 
 	if (editable) {
 		setup_events ();
diff --git a/gtk2_ardour/audio_region_editor.cc b/gtk2_ardour/audio_region_editor.cc
index c95ecc5616..90875a08d4 100644
--- a/gtk2_ardour/audio_region_editor.cc
+++ b/gtk2_ardour/audio_region_editor.cc
@@ -155,7 +155,7 @@ AudioRegionEditor::AudioRegionEditor (Session* s, boost::shared_ptr<AudioRegion>
 	bounds_changed (Change (StartChanged|LengthChanged|PositionChanged|Region::SyncOffsetChanged));
 	gain_changed ();
 
-	_region->StateChanged.connect (state_connection, sigc::mem_fun(*this, &AudioRegionEditor::region_changed));
+	_region->StateChanged.connect (state_connection, ui_bind (&AudioRegionEditor::region_changed, this, _1), gui_context());
 
 	spin_arrow_grab = false;
 
@@ -228,7 +228,8 @@ AudioRegionEditor::connect_editor_events ()
 	gain_adjustment.signal_value_changed().connect (sigc::mem_fun (*this, &AudioRegionEditor::gain_adjustment_changed));
 
 	audition_button.signal_toggled().connect (sigc::mem_fun(*this, &AudioRegionEditor::audition_button_toggled));
-	_session->AuditionActive.connect (audition_connection, sigc::mem_fun(*this, &AudioRegionEditor::audition_state_changed));
+
+	_session->AuditionActive.connect (audition_connection, ui_bind (&AudioRegionEditor::audition_state_changed, this, _1), gui_context());
 }
 
 void
diff --git a/gtk2_ardour/audio_region_view.cc b/gtk2_ardour/audio_region_view.cc
index 3713242101..b8f08456d4 100644
--- a/gtk2_ardour/audio_region_view.cc
+++ b/gtk2_ardour/audio_region_view.cc
@@ -868,7 +868,7 @@ AudioRegionView::create_waves ()
 		// cerr << "\tchannel " << n << endl;
 
 		if (wait_for_data) {
-			if (audio_region()->audio_source(n)->peaks_ready (boost::bind (&AudioRegionView::peaks_ready_handler, this, n), data_ready_connection)) {
+			if (audio_region()->audio_source(n)->peaks_ready (boost::bind (&AudioRegionView::peaks_ready_handler, this, n), data_ready_connection, gui_context())) {
 				// cerr << "\tData is ready\n";
 				create_one_wave (n, true);
 			} else {
@@ -1186,7 +1186,7 @@ AudioRegionView::add_ghost (TimeAxisView& tv)
 	ghost->set_colors();
 	ghosts.push_back (ghost);
 
-	ghost->GoingAway.connect (*this, boost::bind (&RegionView::remove_ghost, this, _1));
+	ghost->GoingAway.connect (*this, ui_bind (&RegionView::remove_ghost, this, _1), gui_context());
 
 	return ghost;
 }
diff --git a/gtk2_ardour/audio_streamview.cc b/gtk2_ardour/audio_streamview.cc
index 6fb481db2d..b95377a58c 100644
--- a/gtk2_ardour/audio_streamview.cc
+++ b/gtk2_ardour/audio_streamview.cc
@@ -66,7 +66,7 @@ AudioStreamView::AudioStreamView (AudioTimeAxisView& tv)
 
 	use_rec_regions = tv.editor().show_waveforms_recording ();
 
-	Config->ParameterChanged.connect (*this, sigc::mem_fun (*this, &AudioStreamView::parameter_changed));
+	Config->ParameterChanged.connect (*this, ui_bind (&AudioStreamView::parameter_changed, this, _1), gui_context());
 }
 
 AudioStreamView::~AudioStreamView ()
@@ -190,7 +190,7 @@ AudioStreamView::add_region_view_internal (boost::shared_ptr<Region> r, bool wai
 
 	/* catch region going away */
 
-	r->GoingAway.connect (*this, boost::bind (&AudioStreamView::remove_region_view, this, boost::weak_ptr<Region> (r)));
+	r->GoingAway.connect (*this, boost::bind (&AudioStreamView::remove_region_view, this, boost::weak_ptr<Region> (r)), gui_context());
 
 	RegionViewAdded (region_view);
 
@@ -288,7 +288,7 @@ AudioStreamView::playlist_changed (boost::shared_ptr<Diskstream> ds)
 	boost::shared_ptr<AudioPlaylist> apl = boost::dynamic_pointer_cast<AudioPlaylist>(ds->playlist());
 
 	if (apl) {
-		apl->NewCrossfade.connect (playlist_connections, boost::bind (&AudioStreamView::add_crossfade, this, _1));
+		apl->NewCrossfade.connect (playlist_connections, ui_bind (&AudioStreamView::add_crossfade, this, _1), gui_context());
 	}
 }
 
@@ -347,7 +347,7 @@ AudioStreamView::add_crossfade (boost::shared_ptr<Crossfade> crossfade)
 					       region_color,
 					       *lview, *rview);
 	cv->set_valid (true);
-	crossfade->Invalidated.connect (*this, sigc::mem_fun (*this, &AudioStreamView::remove_crossfade));
+	crossfade->Invalidated.connect (*this, ui_bind (&AudioStreamView::remove_crossfade, this, _1), gui_context());
 	crossfade_views[cv->crossfade] = cv;
 	if (!_trackview.session()->config.get_xfades_visible() || !crossfades_visible) {
 		cv->hide ();
@@ -482,10 +482,9 @@ AudioStreamView::setup_rec_box ()
 					boost::shared_ptr<AudioFileSource> src = ads->write_source (n);
 					if (src) {
 						sources.push_back (src);
-
-						(src->PeakRangeReady.connect (rec_data_ready_connections,
-									      boost::bind (&AudioStreamView::rec_peak_range_ready, 
-											   this, _1, _2, boost::weak_ptr<Source>(src))));
+						src->PeakRangeReady.connect (rec_data_ready_connections,
+									     ui_bind (&AudioStreamView::rec_peak_range_ready, this, _1, _2, boost::weak_ptr<Source>(src)),
+									     gui_context());
 					}
 				}
 
diff --git a/gtk2_ardour/audio_time_axis.cc b/gtk2_ardour/audio_time_axis.cc
index 0105e1846c..7236c5dea6 100644
--- a/gtk2_ardour/audio_time_axis.cc
+++ b/gtk2_ardour/audio_time_axis.cc
@@ -56,6 +56,7 @@
 #include "canvas_impl.h"
 #include "crossfade_view.h"
 #include "enums.h"
+#include "gui_thread.h"
 #include "automation_time_axis.h"
 #include "keyboard.h"
 #include "playlist_selector.h"
@@ -108,7 +109,7 @@ AudioTimeAxisView::AudioTimeAxisView (PublicEditor& ed, Session* sess, boost::sh
 	}
 
 	if (_route->panner()) {
-		_route->panner()->Changed.connect (*this, (boost::bind (&AudioTimeAxisView::ensure_pan_views, this, false)));
+		_route->panner()->Changed.connect (*this, boost::bind (&AudioTimeAxisView::ensure_pan_views, this, false), gui_context());
 	}
 
 	/* map current state of the route */
diff --git a/gtk2_ardour/automation_controller.cc b/gtk2_ardour/automation_controller.cc
index ba08024161..1a32c36b62 100644
--- a/gtk2_ardour/automation_controller.cc
+++ b/gtk2_ardour/automation_controller.cc
@@ -54,7 +54,7 @@ AutomationController::AutomationController(boost::shared_ptr<AutomationControl>
 	_screen_update_connection = ARDOUR_UI::RapidScreenUpdate.connect (
 			sigc::mem_fun (*this, &AutomationController::display_effective_value));
 
-	ac->Changed.connect (_changed_connection, sigc::mem_fun(*this, &AutomationController::value_changed));
+	ac->Changed.connect (_changed_connection, boost::bind (&AutomationController::value_changed, this), gui_context());
 }
 
 AutomationController::~AutomationController()
diff --git a/gtk2_ardour/automation_line.cc b/gtk2_ardour/automation_line.cc
index 726de984a0..8091e3488f 100644
--- a/gtk2_ardour/automation_line.cc
+++ b/gtk2_ardour/automation_line.cc
@@ -33,6 +33,7 @@
 #include "simplerect.h"
 #include "automation_line.h"
 #include "control_point.h"
+#include "gui_thread.h"
 #include "rgb_macros.h"
 #include "ardour_ui.h"
 #include "public_editor.h"
@@ -85,7 +86,7 @@ AutomationLine::AutomationLine (const string& name, TimeAxisView& tv, ArdourCanv
 
 	line->signal_event().connect (sigc::mem_fun (*this, &AutomationLine::event_handler));
 
-	alist->StateChanged.connect (_state_connection, boost::bind (&AutomationLine::list_changed, this));
+	alist->StateChanged.connect (_state_connection, boost::bind (&AutomationLine::list_changed, this), gui_context());
 
 	trackview.session()->register_with_memento_command_factory(alist->id(), this);
 
diff --git a/gtk2_ardour/automation_region_view.cc b/gtk2_ardour/automation_region_view.cc
index bcb6376027..5e13ee55fd 100644
--- a/gtk2_ardour/automation_region_view.cc
+++ b/gtk2_ardour/automation_region_view.cc
@@ -22,7 +22,9 @@
 #include "ardour/event_type_map.h"
 #include "ardour/session.h"
 #include "ardour/source.h"
+
 #include "automation_region_view.h"
+#include "gui_thread.h"
 #include "public_editor.h"
 
 #include "i18n.h"
@@ -59,7 +61,7 @@ AutomationRegionView::init (Gdk::Color const & basic_color, bool /*wfd*/)
 
 	set_height (trackview.current_height());
 
-	_region->StateChanged.connect (*this, boost::bind (&RegionView::region_changed, this, _1));
+	_region->StateChanged.connect (*this, ui_bind (&RegionView::region_changed, this, _1), gui_context());
 
 	set_colors ();
 
diff --git a/gtk2_ardour/automation_streamview.cc b/gtk2_ardour/automation_streamview.cc
index 731374eb2d..c8dc0ae3c4 100644
--- a/gtk2_ardour/automation_streamview.cc
+++ b/gtk2_ardour/automation_streamview.cc
@@ -129,7 +129,7 @@ AutomationStreamView::add_region_view_internal (boost::shared_ptr<Region> region
 	display_region(region_view);
 
 	/* catch regionview going away */
-	region->GoingAway.connect (*this, boost::bind (&AutomationStreamView::remove_region_view, this, boost::weak_ptr<Region>(region)));
+	region->GoingAway.connect (*this, boost::bind (&AutomationStreamView::remove_region_view, this, boost::weak_ptr<Region>(region)), gui_context());
 
 	RegionViewAdded (region_view);
 
diff --git a/gtk2_ardour/automation_time_axis.cc b/gtk2_ardour/automation_time_axis.cc
index fa507448b4..5454c9991f 100644
--- a/gtk2_ardour/automation_time_axis.cc
+++ b/gtk2_ardour/automation_time_axis.cc
@@ -28,6 +28,7 @@
 #include "ardour_ui.h"
 #include "automation_time_axis.h"
 #include "automation_streamview.h"
+#include "gui_thread.h"
 #include "route_time_axis.h"
 #include "automation_line.h"
 #include "public_editor.h"
@@ -833,7 +834,7 @@ AutomationTimeAxisView::add_line (boost::shared_ptr<AutomationLine> line)
 	assert(!_line);
 	assert(line->the_list() == _control->list());
 
-	_control->alist()->automation_state_changed.connect (automation_connection, boost::bind (&AutomationTimeAxisView::automation_state_changed, this));
+	_control->alist()->automation_state_changed.connect (automation_connection, boost::bind (&AutomationTimeAxisView::automation_state_changed, this), gui_context());
 
 	_line = line;
 	//_controller = AutomationController::create(_session, line->the_list(), _control);
diff --git a/gtk2_ardour/automation_time_axis.h b/gtk2_ardour/automation_time_axis.h
index f00d0a24fe..05e0746bf2 100644
--- a/gtk2_ardour/automation_time_axis.h
+++ b/gtk2_ardour/automation_time_axis.h
@@ -151,7 +151,7 @@ class AutomationTimeAxisView : public TimeAxisView {
 	void set_interpolation (ARDOUR::AutomationList::InterpolationStyle);
 	void interpolation_changed ();
 
-	boost::signals2::scoped_connection automation_connection;
+	PBD::ScopedConnection automation_connection;
 
 	void update_extra_xml_shown (bool editor_shown);
 
diff --git a/gtk2_ardour/bundle_manager.cc b/gtk2_ardour/bundle_manager.cc
index 9b4b2b6bde..a65f5bae35 100644
--- a/gtk2_ardour/bundle_manager.cc
+++ b/gtk2_ardour/bundle_manager.cc
@@ -24,10 +24,12 @@
 #include <gtkmm/table.h>
 #include <gtkmm/comboboxtext.h>
 #include <gtkmm/alignment.h>
+
 #include "ardour/session.h"
 #include "ardour/user_bundle.h"
 #include "ardour/audioengine.h"
 #include "bundle_manager.h"
+#include "gui_thread.h"
 #include "i18n.h"
 #include "utils.h"
 
@@ -395,7 +397,7 @@ BundleManager::add_bundle (boost::shared_ptr<Bundle> b)
 	(*i)[_list_model_columns.name] = u->name ();
 	(*i)[_list_model_columns.bundle] = u;
 
-	u->Changed.connect (bundle_connections, boost::bind (&BundleManager::bundle_changed, this, _1, u));
+	u->Changed.connect (bundle_connections, ui_bind (&BundleManager::bundle_changed, this, _1, u), gui_context());
 }
 
 void
@@ -420,7 +422,7 @@ BundleManager::bundle_changed (Bundle::Change c, boost::shared_ptr<UserBundle> b
 }
 
 void
-BundleManager::row_activated (Gtk::TreeModel::Path const & p, Gtk::TreeViewColumn* c)
+BundleManager::row_activated (Gtk::TreeModel::Path const & p, Gtk::TreeViewColumn*)
 {
 	Gtk::TreeModel::iterator i = _list_model->get_iter (p);
 	if (!i) {
diff --git a/gtk2_ardour/crossfade_edit.cc b/gtk2_ardour/crossfade_edit.cc
index afb595938d..fd651599ea 100644
--- a/gtk2_ardour/crossfade_edit.cc
+++ b/gtk2_ardour/crossfade_edit.cc
@@ -291,9 +291,9 @@ CrossfadeEditor::CrossfadeEditor (Session* s, boost::shared_ptr<Crossfade> xf, d
 
 	curve_select_clicked (In);
 
-	xfade->StateChanged.connect (state_connection, boost::bind (&CrossfadeEditor::xfade_changed, this, _1));
+	xfade->StateChanged.connect (state_connection, ui_bind (&CrossfadeEditor::xfade_changed, this, _1), gui_context());
 
-	_session->AuditionActive.connect (_session_connections, sigc::mem_fun(*this, &CrossfadeEditor::audition_state_changed));
+	_session->AuditionActive.connect (_session_connections, ui_bind (&CrossfadeEditor::audition_state_changed, this, _1), gui_context());
 	show_all_children();
 }
 
@@ -1130,7 +1130,7 @@ CrossfadeEditor::make_waves (boost::shared_ptr<AudioRegion> region, WhichFade wh
 
 		gdouble yoff = n * ht;
 
-		if (region->audio_source(n)->peaks_ready (boost::bind (&CrossfadeEditor::peaks_ready, this, boost::weak_ptr<AudioRegion>(region), which), peaks_ready_connection)) {
+		if (region->audio_source(n)->peaks_ready (boost::bind (&CrossfadeEditor::peaks_ready, this, boost::weak_ptr<AudioRegion>(region), which), peaks_ready_connection, gui_context())) {
 			WaveView* waveview = new WaveView (*(canvas->root()));
 
 			waveview->property_data_src() = region.get();
diff --git a/gtk2_ardour/crossfade_view.cc b/gtk2_ardour/crossfade_view.cc
index 3a34ace7fa..41134e5096 100644
--- a/gtk2_ardour/crossfade_view.cc
+++ b/gtk2_ardour/crossfade_view.cc
@@ -25,6 +25,7 @@
 #include "canvas-simplerect.h"
 #include "canvas-curve.h"
 #include "crossfade_view.h"
+#include "gui_thread.h"
 #include "rgb_macros.h"
 #include "audio_time_axis.h"
 #include "public_editor.h"
@@ -83,7 +84,7 @@ CrossfadeView::CrossfadeView (ArdourCanvas::Group *parent,
 
 	crossfade_changed (Change (~0));
 
-	crossfade->StateChanged.connect (*this, sigc::mem_fun(*this, &CrossfadeView::crossfade_changed));
+	crossfade->StateChanged.connect (*this, ui_bind (&CrossfadeView::crossfade_changed, this, _1), gui_context());
 	ColorsChanged.connect (sigc::mem_fun (*this, &CrossfadeView::color_handler));
 }
 
diff --git a/gtk2_ardour/editor.cc b/gtk2_ardour/editor.cc
index 9bf2ccbc5d..8b98273229 100644
--- a/gtk2_ardour/editor.cc
+++ b/gtk2_ardour/editor.cc
@@ -627,7 +627,7 @@ Editor::Editor ()
 	_playlist_selector = new PlaylistSelector();
 	_playlist_selector->signal_delete_event().connect (sigc::bind (sigc::ptr_fun (just_hide_it), static_cast<Window *> (_playlist_selector)));
 
-	RegionView::RegionViewGoingAway.connect (*this, boost::bind (&Editor::catch_vanishing_regionview, this, _1));
+	RegionView::RegionViewGoingAway.connect (*this, ui_bind (&Editor::catch_vanishing_regionview, this, _1), gui_context());
 
 	/* nudge stuff */
 
@@ -677,14 +677,17 @@ Editor::Editor ()
 
 	/* allow external control surfaces/protocols to do various things */
 
-	ControlProtocol::ZoomToSession.connect (*this, boost::bind (&Editor::temporal_zoom_session, this));
-	ControlProtocol::ZoomIn.connect (*this, boost::bind (&Editor::temporal_zoom_step, this, false));
-	ControlProtocol::ZoomOut.connect (*this, boost::bind (&Editor::temporal_zoom_step, this, true));
-	ControlProtocol::ScrollTimeline.connect (*this, boost::bind (&Editor::control_scroll, this, _1));
-	BasicUI::AccessAction.connect (*this, boost::bind (&Editor::access_action, this, _1, _2));
-	Session::AskAboutPlaylistDeletion.connect (*this, boost::bind (&Editor::playlist_deletion_dialog, this, _1));
+	ControlProtocol::ZoomToSession.connect (*this, boost::bind (&Editor::temporal_zoom_session, this), gui_context());
+	ControlProtocol::ZoomIn.connect (*this, boost::bind (&Editor::temporal_zoom_step, this, false), gui_context());
+	ControlProtocol::ZoomOut.connect (*this, boost::bind (&Editor::temporal_zoom_step, this, true), gui_context());
+	ControlProtocol::ScrollTimeline.connect (*this, ui_bind (&Editor::control_scroll, this, _1), gui_context());
+	BasicUI::AccessAction.connect (*this, ui_bind (&Editor::access_action, this, _1, _2), gui_context());
+	
+	/* problematic: has to return a value and thus cannot be x-thread */
+
+	Session::AskAboutPlaylistDeletion.connect_same_thread (*this, boost::bind (&Editor::playlist_deletion_dialog, this, _1));
 
-	Config->ParameterChanged.connect (*this, boost::bind (&Editor::parameter_changed, this, _1));
+	Config->ParameterChanged.connect (*this, ui_bind (&Editor::parameter_changed, this, _1), gui_context());
 
 	_last_normalization_value = 0;
 
@@ -1081,22 +1084,22 @@ Editor::set_session (Session *t)
 	   but use Gtkmm2ext::UI::instance()->call_slot();
 	*/
 
-	_session->TransportStateChange.connect (_session_connections, boost::bind (&Editor::map_transport_state, this));
-	_session->PositionChanged.connect (_session_connections, boost::bind (&Editor::map_position_change, this, _1));
-	_session->RouteAdded.connect (_session_connections, boost::bind (&Editor::handle_new_route, this, _1));
-	_session->DurationChanged.connect (_session_connections, boost::bind (&Editor::handle_new_duration, this));
-	_session->DirtyChanged.connect (_session_connections, boost::bind (&Editor::update_title, this));
-	_session->TimecodeOffsetChanged.connect (_session_connections, boost::bind (&Editor::update_just_timecode, this));
-	_session->tempo_map().StateChanged.connect (_session_connections, boost::bind (&Editor::tempo_map_changed, this, _1));
-	_session->Located.connect (_session_connections, boost::bind (&Editor::located, this));
-	_session->config.ParameterChanged.connect (_session_connections, boost::bind (&Editor::parameter_changed, this, _1));
-	_session->StateSaved.connect (_session_connections, boost::bind (&Editor::session_state_saved, this, _1));
-	_session->locations()->added.connect (_session_connections, sigc::mem_fun(*this, &Editor::add_new_location));
-	_session->locations()->removed.connect (_session_connections, sigc::mem_fun(*this, &Editor::location_gone));
-	_session->locations()->changed.connect (_session_connections, sigc::mem_fun(*this, &Editor::refresh_location_display));
-	_session->locations()->StateChanged.connect (_session_connections, sigc::mem_fun(*this, &Editor::refresh_location_display_s));
-	_session->locations()->end_location()->changed.connect (_session_connections, sigc::mem_fun(*this, &Editor::end_location_changed));
-	_session->history().Changed.connect (_session_connections, boost::bind (&Editor::history_changed, this));
+	_session->TransportStateChange.connect (_session_connections, boost::bind (&Editor::map_transport_state, this), gui_context());
+	_session->PositionChanged.connect (_session_connections, ui_bind (&Editor::map_position_change, this, _1), gui_context());
+	_session->RouteAdded.connect (_session_connections, ui_bind (&Editor::handle_new_route, this, _1), gui_context());
+	_session->DurationChanged.connect (_session_connections, boost::bind (&Editor::handle_new_duration, this), gui_context());
+	_session->DirtyChanged.connect (_session_connections, boost::bind (&Editor::update_title, this), gui_context());
+	_session->TimecodeOffsetChanged.connect (_session_connections, boost::bind (&Editor::update_just_timecode, this), gui_context());
+	_session->tempo_map().StateChanged.connect (_session_connections, ui_bind (&Editor::tempo_map_changed, this, _1), gui_context());
+	_session->Located.connect (_session_connections, boost::bind (&Editor::located, this), gui_context());
+	_session->config.ParameterChanged.connect (_session_connections, ui_bind (&Editor::parameter_changed, this, _1), gui_context());
+	_session->StateSaved.connect (_session_connections, ui_bind (&Editor::session_state_saved, this, _1), gui_context());
+	_session->locations()->added.connect (_session_connections, ui_bind (&Editor::add_new_location, this, _1), gui_context());
+	_session->locations()->removed.connect (_session_connections, ui_bind (&Editor::location_gone, this, _1), gui_context());
+	_session->locations()->changed.connect (_session_connections, boost::bind (&Editor::refresh_location_display, this), gui_context());
+	_session->locations()->StateChanged.connect (_session_connections, ui_bind (&Editor::refresh_location_display_s, this, _1), gui_context());
+	_session->locations()->end_location()->changed.connect (_session_connections, ui_bind (&Editor::end_location_changed, this, _1), gui_context());
+	_session->history().Changed.connect (_session_connections, boost::bind (&Editor::history_changed, this), gui_context());
 
 	if (Profile->get_sae()) {
 		BBT_Time bbt;
@@ -4802,7 +4805,7 @@ Editor::handle_new_route (RouteList& routes)
 		rtv->view()->RegionViewAdded.connect (sigc::mem_fun (*this, &Editor::region_view_added));
 		rtv->view()->HeightChanged.connect (sigc::mem_fun (*this, &Editor::streamview_height_changed));
 
-		rtv->GoingAway.connect (*this, boost::bind (&Editor::remove_route, this, rtv));
+		rtv->GoingAway.connect (*this, boost::bind (&Editor::remove_route, this, rtv), gui_context());
 	}
 
 	_routes->routes_added (new_views);
diff --git a/gtk2_ardour/editor_drag.cc b/gtk2_ardour/editor_drag.cc
index 4f864309f9..907abfc348 100644
--- a/gtk2_ardour/editor_drag.cc
+++ b/gtk2_ardour/editor_drag.cc
@@ -30,6 +30,7 @@
 #include "audio_region_view.h"
 #include "midi_region_view.h"
 #include "ardour_ui.h"
+#include "gui_thread.h"
 #include "control_point.h"
 #include "utils.h"
 #include "region_gain_line.h"
@@ -237,7 +238,7 @@ RegionDrag::RegionDrag (Editor* e, ArdourCanvas::Item* i, RegionView* p, list<Re
 	  _primary (p),
 	  _views (v)
 {
-	RegionView::RegionViewGoingAway.connect (death_connection, boost::bind (&RegionDrag::region_going_away, this, _1));
+	RegionView::RegionViewGoingAway.connect (death_connection, ui_bind (&RegionDrag::region_going_away, this, _1), gui_context());
 }
 
 void
diff --git a/gtk2_ardour/editor_drag.h b/gtk2_ardour/editor_drag.h
index 170c9a8080..95b22221a3 100644
--- a/gtk2_ardour/editor_drag.h
+++ b/gtk2_ardour/editor_drag.h
@@ -160,7 +160,7 @@ protected:
 
 private:
 	void region_going_away (RegionView *);
-	boost::signals2::scoped_connection death_connection;
+	PBD::ScopedConnection death_connection;
 };
 
 
diff --git a/gtk2_ardour/editor_imageframe.cc b/gtk2_ardour/editor_imageframe.cc
index 7f499c0c6f..4b0601fcea 100644
--- a/gtk2_ardour/editor_imageframe.cc
+++ b/gtk2_ardour/editor_imageframe.cc
@@ -41,6 +41,7 @@
 #include "imageframe_socket_handler.h"
 #include "ardour_image_compositor_socket.h"
 #include "public_editor.h"
+#include "gui_thread.h"
 
 using namespace Gtk;
 using namespace PBD;
@@ -1092,7 +1093,7 @@ Editor::handle_new_imageframe_time_axis_view(const string & track_name, void* sr
 	row[route_display_columns.tv] = iftav;
 	route_list_display.get_selection()->select (row);
 
-	iftav->GoingAway.connect (*this, boost::bind (&Editor::remove_route, this, (TimeAxisView*)iftav));
+	iftav->GoingAway.connect (*this, boost::bind (&Editor::remove_route, this, (TimeAxisView*)iftav), gui_context());
 	iftav->gui_changed.connect(sigc::mem_fun(*this, &Editor::handle_gui_changes)) ;
 }
 
@@ -1109,7 +1110,7 @@ Editor::handle_new_imageframe_marker_time_axis_view(const string & track_name, T
 	row[route_display_columns.tv] = mta;
 	route_list_display.get_selection()->select (row);
 
-	mta->GoingAway.connect (*this, boost::bind (&Editor::remove_route, this, (TimeAxisView*)mta));
+	mta->GoingAway.connect (*this, boost::bind (&Editor::remove_route, this, (TimeAxisView*)mta), gui_context());
  }
 
 
diff --git a/gtk2_ardour/editor_markers.cc b/gtk2_ardour/editor_markers.cc
index dbee2fb9d2..79fd056126 100644
--- a/gtk2_ardour/editor_markers.cc
+++ b/gtk2_ardour/editor_markers.cc
@@ -123,11 +123,11 @@ Editor::add_new_location (Location *location)
 		lam->show ();
 	}
 
-	location->start_changed.connect (*this, boost::bind (&Editor::location_changed, this, _1));
-	location->end_changed.connect (*this, boost::bind (&Editor::location_changed, this, _1));
-	location->changed.connect (*this, boost::bind (&Editor::location_changed, this, _1));
-	location->name_changed.connect (*this, boost::bind (&Editor::location_changed, this, _1));
-	location->FlagsChanged.connect (*this, boost::bind (&Editor::location_flags_changed, this, _1, _2));
+	location->start_changed.connect (*this, ui_bind (&Editor::location_changed, this, _1), gui_context());
+	location->end_changed.connect (*this, ui_bind (&Editor::location_changed, this, _1), gui_context());
+	location->changed.connect (*this, ui_bind (&Editor::location_changed, this, _1), gui_context());
+	location->name_changed.connect (*this, ui_bind (&Editor::location_changed, this, _1), gui_context());
+	location->FlagsChanged.connect (*this, ui_bind (&Editor::location_flags_changed, this, _1, _2), gui_context());
 
 	pair<Location*,LocationMarkers*> newpair;
 
diff --git a/gtk2_ardour/editor_mixer.cc b/gtk2_ardour/editor_mixer.cc
index 6cb6046006..64d9e97ac6 100644
--- a/gtk2_ardour/editor_mixer.cc
+++ b/gtk2_ardour/editor_mixer.cc
@@ -35,6 +35,7 @@
 #include "editor_routes.h"
 #include "editor_route_groups.h"
 #include "editor_regions.h"
+#include "gui_thread.h"
 
 #include "i18n.h"
 
@@ -168,7 +169,7 @@ Editor::create_editor_mixer ()
 					      _session,
 					      false);
 	current_mixer_strip->Hiding.connect (sigc::mem_fun(*this, &Editor::current_mixer_strip_hidden));
-	current_mixer_strip->GoingAway.connect (*this, boost::bind (&Editor::current_mixer_strip_removed, this));
+	current_mixer_strip->GoingAway.connect (*this, boost::bind (&Editor::current_mixer_strip_removed, this), gui_context());
 #ifdef GTKOSX
 	current_mixer_strip->WidthChanged.connect (sigc::mem_fun(*this, &Editor::ensure_all_elements_drawn));
 #endif
diff --git a/gtk2_ardour/editor_regions.cc b/gtk2_ardour/editor_regions.cc
index 26ae2f6f50..490f6991e3 100644
--- a/gtk2_ardour/editor_regions.cc
+++ b/gtk2_ardour/editor_regions.cc
@@ -125,7 +125,7 @@ EditorRegions::EditorRegions (Editor* e)
 
 	//ARDOUR_UI::instance()->secondary_clock.mode_changed.connect (sigc::mem_fun(*this, &Editor::redisplay_regions));
 	ARDOUR_UI::instance()->secondary_clock.mode_changed.connect (sigc::mem_fun(*this, &EditorRegions::update_all_rows));
-	ARDOUR::Region::RegionPropertyChanged.connect (region_property_connection, sigc::mem_fun(*this, &EditorRegions::update_row));
+	ARDOUR::Region::RegionPropertyChanged.connect (region_property_connection, ui_bind (&EditorRegions::update_row, this, _1), gui_context());
 
 }
 
@@ -135,9 +135,9 @@ EditorRegions::set_session (ARDOUR::Session* s)
 	EditorComponent::set_session (s);
 
 	if (_session) {
-		_session->RegionsAdded.connect (_session_connections, boost::bind (&EditorRegions::handle_new_regions, this, _1));
-		_session->RegionRemoved.connect (_session_connections, boost::bind (&EditorRegions::handle_region_removed, this, _1));
-		_session->RegionHiddenChange.connect (_session_connections, boost::bind (&EditorRegions::region_hidden, this, _1));
+		_session->RegionsAdded.connect (_session_connections, ui_bind (&EditorRegions::handle_new_regions, this, _1), gui_context());
+		_session->RegionRemoved.connect (_session_connections, ui_bind (&EditorRegions::handle_region_removed, this, _1), gui_context());
+		_session->RegionHiddenChange.connect (_session_connections, ui_bind (&EditorRegions::region_hidden, this, _1), gui_context());
 	}
 
 	redisplay ();
diff --git a/gtk2_ardour/editor_route_groups.cc b/gtk2_ardour/editor_route_groups.cc
index c52817a15a..9cbb2725c2 100644
--- a/gtk2_ardour/editor_route_groups.cc
+++ b/gtk2_ardour/editor_route_groups.cc
@@ -574,7 +574,7 @@ EditorRouteGroups::add (RouteGroup* group)
 		focus = true;
 	}
 
-	group->FlagsChanged.connect (flags_connection, boost::bind (&EditorRouteGroups::flags_changed, this, _1, group));
+	group->FlagsChanged.connect (flags_connection, ui_bind (&EditorRouteGroups::flags_changed, this, _1, group), gui_context());
 
 	if (focus) {
 		TreeViewColumn* col = _display.get_column (0);
@@ -668,8 +668,8 @@ EditorRouteGroups::set_session (Session* s)
 	EditorComponent::set_session (s);
 
 	if (_session) {
-		_session->route_group_added.connect (_session_connections, boost::bind (&EditorRouteGroups::add, this, _1));
-		_session->route_group_removed.connect (_session_connections, boost::bind (&EditorRouteGroups::groups_changed, this));
+		_session->route_group_added.connect (_session_connections, ui_bind (&EditorRouteGroups::add, this, _1), gui_context());
+		_session->route_group_removed.connect (_session_connections, boost::bind (&EditorRouteGroups::groups_changed, this), gui_context());
 	}
 
 	groups_changed ();
diff --git a/gtk2_ardour/editor_routes.cc b/gtk2_ardour/editor_routes.cc
index 3ef66161fb..b18d35a5e3 100644
--- a/gtk2_ardour/editor_routes.cc
+++ b/gtk2_ardour/editor_routes.cc
@@ -150,7 +150,7 @@ EditorRoutes::EditorRoutes (Editor* e)
 	_model->signal_rows_reordered().connect (sigc::mem_fun (*this, &EditorRoutes::reordered));
 	_display.signal_button_press_event().connect (sigc::mem_fun (*this, &EditorRoutes::button_press), false);
 
-	Route::SyncOrderKeys.connect (*this, (sigc::mem_fun (*this, &EditorRoutes::sync_order_keys)));
+	Route::SyncOrderKeys.connect (*this, ui_bind (&EditorRoutes::sync_order_keys, this, _1), gui_context());
 }
 
 void
@@ -161,7 +161,7 @@ EditorRoutes::set_session (Session* s)
 	initial_display ();
 
 	if (_session) {
-		_session->SoloChanged.connect (*this, (sigc::mem_fun (*this, &EditorRoutes::solo_changed_so_update_mute)));
+		_session->SoloChanged.connect (*this, boost::bind (&EditorRoutes::solo_changed_so_update_mute, this), gui_context());
 	}
 }
 
@@ -383,18 +383,18 @@ EditorRoutes::routes_added (list<RouteTimeAxisView*> routes)
 
 		boost::weak_ptr<Route> wr ((*x)->route());
 
-		(*x)->route()->gui_changed.connect (*this, boost::bind (&EditorRoutes::handle_gui_changes, this, _1, _2));
-		(*x)->route()->NameChanged.connect (*this, boost::bind (&EditorRoutes::route_name_changed, this, wr));
-		(*x)->GoingAway.connect (*this, boost::bind (&EditorRoutes::route_removed, this, *x));
+		(*x)->route()->gui_changed.connect (*this, ui_bind (&EditorRoutes::handle_gui_changes, this, _1, _2), gui_context());
+		(*x)->route()->NameChanged.connect (*this, boost::bind (&EditorRoutes::route_name_changed, this, wr), gui_context());
+		(*x)->GoingAway.connect (*this, boost::bind (&EditorRoutes::route_removed, this, *x), gui_context());
 
 		if ((*x)->is_track()) {
 			boost::shared_ptr<Track> t = boost::dynamic_pointer_cast<Track> ((*x)->route());
-			t->diskstream()->RecordEnableChanged.connect (*this, boost::bind (&EditorRoutes::update_rec_display, this));
+			t->diskstream()->RecordEnableChanged.connect (*this, boost::bind (&EditorRoutes::update_rec_display, this), gui_context());
 		}
 
-		(*x)->route()->mute_changed.connect (*this, boost::bind (&EditorRoutes::update_mute_display, this));
-		(*x)->route()->solo_changed.connect (*this, boost::bind (&EditorRoutes::update_solo_display, this));
-		(*x)->route()->solo_isolated_changed.connect (*this, boost::bind (&EditorRoutes::update_solo_isolate_display, this));
+		(*x)->route()->mute_changed.connect (*this, boost::bind (&EditorRoutes::update_mute_display, this), gui_context());
+		(*x)->route()->solo_changed.connect (*this, boost::bind (&EditorRoutes::update_solo_display, this), gui_context());
+		(*x)->route()->solo_isolated_changed.connect (*this, boost::bind (&EditorRoutes::update_solo_isolate_display, this), gui_context());
 	}
 
 	update_rec_display ();
diff --git a/gtk2_ardour/editor_summary.cc b/gtk2_ardour/editor_summary.cc
index 93be5afd13..aae814d8e5 100644
--- a/gtk2_ardour/editor_summary.cc
+++ b/gtk2_ardour/editor_summary.cc
@@ -47,8 +47,8 @@ EditorSummary::EditorSummary (Editor* e)
 	  _zoom_dragging (false)
 
 {
-	Region::RegionPropertyChanged.connect (region_property_connection, boost::bind (&CairoWidget::set_dirty, this));
-	_editor->playhead_cursor->PositionChanged.connect (position_connection, boost::bind (&EditorSummary::playhead_position_changed, this, _1));
+	Region::RegionPropertyChanged.connect (region_property_connection, boost::bind (&CairoWidget::set_dirty, this), gui_context());
+	_editor->playhead_cursor->PositionChanged.connect (position_connection, ui_bind (&EditorSummary::playhead_position_changed, this, _1), gui_context());
 }
 
 /** Connect to a session.
@@ -62,9 +62,9 @@ EditorSummary::set_session (Session* s)
 	set_dirty ();
 
 	if (_session) {
-		_session->RegionRemoved.connect (_session_connections, boost::bind (&EditorSummary::set_dirty, this));
-		_session->StartTimeChanged.connect (_session_connections, boost::bind (&EditorSummary::set_dirty, this));
-		_session->EndTimeChanged.connect (_session_connections, boost::bind (&EditorSummary::set_dirty, this));
+		_session->RegionRemoved.connect (_session_connections, boost::bind (&EditorSummary::set_dirty, this), gui_context());
+		_session->StartTimeChanged.connect (_session_connections, boost::bind (&EditorSummary::set_dirty, this), gui_context());
+		_session->EndTimeChanged.connect (_session_connections, boost::bind (&EditorSummary::set_dirty, this), gui_context());
 	}
 }
 
diff --git a/gtk2_ardour/export_dialog.cc b/gtk2_ardour/export_dialog.cc
index 84202d57ea..0f5c6a4551 100644
--- a/gtk2_ardour/export_dialog.cc
+++ b/gtk2_ardour/export_dialog.cc
@@ -18,7 +18,6 @@
 
 */
 
-#include "export_dialog.h"
 
 #include <sigc++/signal.h>
 
@@ -27,6 +26,9 @@
 #include "ardour/export_status.h"
 #include "ardour/export_handler.h"
 
+#include "export_dialog.h"
+#include "gui_thread.h"
+
 using namespace ARDOUR;
 using namespace PBD;
 
@@ -86,7 +88,8 @@ ExportDialog::set_session (ARDOUR::Session* s)
 	timespan_selector->CriticalSelectionChanged.connect (sigc::mem_fun (*this, &ExportDialog::update_warnings));
 	channel_selector->CriticalSelectionChanged.connect (sigc::mem_fun (*this, &ExportDialog::update_warnings));
 	file_notebook->CriticalSelectionChanged.connect (sigc::mem_fun (*this, &ExportDialog::update_warnings));
-	status->Aborting.connect (abort_connection, sigc::mem_fun (*this, &ExportDialog::notify_errors));
+
+	status->Aborting.connect (abort_connection, boost::bind (&ExportDialog::notify_errors, this), gui_context());
 
 	update_warnings ();
 }
diff --git a/gtk2_ardour/export_file_notebook.cc b/gtk2_ardour/export_file_notebook.cc
index 5961715d83..c785d14be1 100644
--- a/gtk2_ardour/export_file_notebook.cc
+++ b/gtk2_ardour/export_file_notebook.cc
@@ -22,6 +22,7 @@
 
 #include "ardour/export_format_specification.h"
 
+#include "gui_thread.h"
 #include "utils.h"
 #include "i18n.h"
 
@@ -196,7 +197,7 @@ ExportFileNotebook::FilePage::FilePage (Session * s, ManagerPtr profile_manager,
 
 	tab_close_button.signal_clicked().connect (sigc::bind (sigc::mem_fun (*parent, &ExportFileNotebook::remove_file_page), this));
 
-	profile_manager->FormatListChanged.connect (format_connection, boost::bind (&ExportFormatSelector::update_format_list, &format_selector));
+	profile_manager->FormatListChanged.connect (format_connection, boost::bind (&ExportFormatSelector::update_format_list, &format_selector), gui_context());
 
 	format_selector.FormatEdited.connect (sigc::mem_fun (*this, &ExportFileNotebook::FilePage::save_format_to_manager));
 	format_selector.FormatRemoved.connect (sigc::mem_fun (*profile_manager, &ExportProfileManager::remove_format_profile));
diff --git a/gtk2_ardour/export_format_dialog.cc b/gtk2_ardour/export_format_dialog.cc
index 1c93115da3..1b0a511ac3 100644
--- a/gtk2_ardour/export_format_dialog.cc
+++ b/gtk2_ardour/export_format_dialog.cc
@@ -18,11 +18,11 @@
 
 */
 
-#include "export_format_dialog.h"
-
 #include "ardour/session.h"
 #include "ardour/export_format_specification.h"
 
+#include "export_format_dialog.h"
+#include "gui_thread.h"
 #include "i18n.h"
 
 using namespace ARDOUR;
@@ -127,7 +127,7 @@ ExportFormatDialog::ExportFormatDialog (FormatPtr format, bool new_dialog) :
 	close_button = add_button (Gtk::Stock::SAVE, Gtk::RESPONSE_APPLY);
 	close_button->set_sensitive (false);
 	close_button->signal_clicked().connect (sigc::mem_fun (*this, &ExportFormatDialog::end_dialog));
-	manager.CompleteChanged.connect (*this, sigc::mem_fun (close_button, &Gtk::Button::set_sensitive));
+	manager.CompleteChanged.connect (*this, ui_bind (&Gtk::Button::set_sensitive, close_button, _1), gui_context());
 
 	/* Load state before hooking up the rest of the signals */
 
@@ -319,7 +319,7 @@ ExportFormatDialog::init_format_table ()
 		row[compatibility_cols.label] = (*it)->name();
 
 		WeakCompatPtr ptr (*it);
-		(*it)->SelectChanged.connect (*this, boost::bind (&ExportFormatDialog::change_compatibility_selection, this, _1, ptr));
+		(*it)->SelectChanged.connect (*this, ui_bind (&ExportFormatDialog::change_compatibility_selection, this, _1, ptr), gui_context());
 	}
 
 	compatibility_view.append_column_editable ("", compatibility_cols.selected);
@@ -347,8 +347,8 @@ ExportFormatDialog::init_format_table ()
 		row[quality_cols.label] = (*it)->name();
 
 		WeakQualityPtr ptr (*it);
-		(*it)->SelectChanged.connect (*this, boost::bind (&ExportFormatDialog::change_quality_selection, this, _1, ptr));
-		(*it)->CompatibleChanged.connect (*this, boost::bind (&ExportFormatDialog::change_quality_compatibility, this, _1, ptr));
+		(*it)->SelectChanged.connect (*this, ui_bind (&ExportFormatDialog::change_quality_selection, this, _1, ptr), gui_context());
+		(*it)->CompatibleChanged.connect (*this, ui_bind (&ExportFormatDialog::change_quality_compatibility, this, _1, ptr), gui_context());
 	}
 
 	quality_view.append_column ("", quality_cols.label);
@@ -369,19 +369,19 @@ ExportFormatDialog::init_format_table ()
 		row[format_cols.label] = (*it)->name();
 
 		WeakFormatPtr ptr (*it);
-		(*it)->SelectChanged.connect (*this, boost::bind (&ExportFormatDialog::change_format_selection, this, _1, ptr));
-		(*it)->CompatibleChanged.connect (*this, boost::bind (&ExportFormatDialog::change_format_compatibility, this, _1, ptr));
+		(*it)->SelectChanged.connect (*this, ui_bind (&ExportFormatDialog::change_format_selection, this, _1, ptr), gui_context());
+		(*it)->CompatibleChanged.connect (*this, ui_bind (&ExportFormatDialog::change_format_compatibility, this, _1, ptr), gui_context());
 
 		/* Encoding options */
 
 		boost::shared_ptr<HasSampleFormat> hsf;
 
 		if (hsf = boost::dynamic_pointer_cast<HasSampleFormat> (*it)) {
-			hsf->SampleFormatSelectChanged.connect (*this, boost::bind (&ExportFormatDialog::change_sample_format_selection, this, _1, _2));
-			hsf->SampleFormatCompatibleChanged.connect (*this, boost::bind (&ExportFormatDialog::change_sample_format_compatibility, this, _1, _2));
+			hsf->SampleFormatSelectChanged.connect (*this, ui_bind (&ExportFormatDialog::change_sample_format_selection, this, _1, _2), gui_context());
+			hsf->SampleFormatCompatibleChanged.connect (*this, ui_bind (&ExportFormatDialog::change_sample_format_compatibility, this, _1, _2), gui_context());
 
-			hsf->DitherTypeSelectChanged.connect (*this, boost::bind (&ExportFormatDialog::change_dither_type_selection, this, _1, _2));
-			hsf->DitherTypeCompatibleChanged.connect (*this, boost::bind (&ExportFormatDialog::change_dither_type_compatibility, this, _1, _2));
+			hsf->DitherTypeSelectChanged.connect (*this, ui_bind (&ExportFormatDialog::change_dither_type_selection, this, _1, _2), gui_context());
+			hsf->DitherTypeCompatibleChanged.connect (*this, ui_bind (&ExportFormatDialog::change_dither_type_compatibility, this, _1, _2), gui_context());
 		}
 	}
 
@@ -403,8 +403,8 @@ ExportFormatDialog::init_format_table ()
 		row[sample_rate_cols.label] = (*it)->name();
 		
 		WeakSampleRatePtr ptr (*it);
-		(*it)->SelectChanged.connect (*this, boost::bind (&ExportFormatDialog::change_sample_rate_selection, this, _1, ptr));
-		(*it)->CompatibleChanged.connect (*this, boost::bind (&ExportFormatDialog::change_sample_rate_compatibility, this, _1, ptr));
+		(*it)->SelectChanged.connect (*this, ui_bind (&ExportFormatDialog::change_sample_rate_selection, this, _1, ptr), gui_context());
+		(*it)->CompatibleChanged.connect (*this, ui_bind (&ExportFormatDialog::change_sample_rate_compatibility, this, _1, ptr), gui_context());
 	}
 
 	sample_rate_view.append_column ("", sample_rate_cols.label);
diff --git a/gtk2_ardour/gain_meter.cc b/gtk2_ardour/gain_meter.cc
index 3c3b70c7cf..961ceb6a4a 100644
--- a/gtk2_ardour/gain_meter.cc
+++ b/gtk2_ardour/gain_meter.cc
@@ -226,13 +226,13 @@ GainMeterBase::set_controls (boost::shared_ptr<Route> r,
 
 		boost::shared_ptr<AutomationControl> gc = amp->gain_control();
 		
-		gc->alist()->automation_state_changed.connect (model_connections, boost::bind (&GainMeter::gain_automation_state_changed, this));
-		gc->alist()->automation_style_changed.connect (model_connections, boost::bind (&GainMeter::gain_automation_style_changed, this));
+		gc->alist()->automation_state_changed.connect (model_connections, boost::bind (&GainMeter::gain_automation_state_changed, this), gui_context());
+		gc->alist()->automation_style_changed.connect (model_connections, boost::bind (&GainMeter::gain_automation_style_changed, this), gui_context());
 		
 		gain_automation_state_changed ();
 	}
 	
-	amp->gain_control()->Changed.connect (model_connections, boost::bind (&GainMeterBase::gain_changed, this));
+	amp->gain_control()->Changed.connect (model_connections, boost::bind (&GainMeterBase::gain_changed, this), gui_context());
 
 	gain_changed ();
 	show_gain ();
diff --git a/gtk2_ardour/generic_pluginui.cc b/gtk2_ardour/generic_pluginui.cc
index 1865c1e0a2..3d59910ff4 100644
--- a/gtk2_ardour/generic_pluginui.cc
+++ b/gtk2_ardour/generic_pluginui.cc
@@ -125,7 +125,7 @@ GenericPluginUI::GenericPluginUI (boost::shared_ptr<PluginInsert> pi, bool scrol
 		main_contents.pack_start (hpacker, false, false);
 	}
 
-	pi->ActiveChanged.connect (active_connection, boost::bind (&GenericPluginUI::processor_active_changed, this, boost::weak_ptr<Processor>(pi)));
+	pi->ActiveChanged.connect (active_connection, boost::bind (&GenericPluginUI::processor_active_changed, this, boost::weak_ptr<Processor>(pi)), gui_context());
 
 	bypass_button.set_active (!pi->active());
 
@@ -420,7 +420,7 @@ GenericPluginUI::build_control_ui (guint32 port_index, boost::shared_ptr<Automat
 				//control_ui->combo->set_value_in_list(true, false);
 				set_popdown_strings (*control_ui->combo, setup_scale_values(port_index, control_ui));
 				control_ui->combo->signal_changed().connect (sigc::bind (sigc::mem_fun(*this, &GenericPluginUI::control_combo_changed), control_ui));
-				mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::parameter_changed, this, control_ui));
+				mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::parameter_changed, this, control_ui), gui_context());
 				control_ui->pack_start(control_ui->label, true, true);
 				control_ui->pack_start(*control_ui->combo, false, true);
 
@@ -441,7 +441,7 @@ GenericPluginUI::build_control_ui (guint32 port_index, boost::shared_ptr<Automat
 				//control_ui->combo->set_value_in_list(true, false);
 				set_popdown_strings (*control_ui->combo, setup_scale_values(port_index, control_ui));
 				control_ui->combo->signal_changed().connect (sigc::bind (sigc::mem_fun(*this, &GenericPluginUI::control_combo_changed), control_ui));
-				mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::parameter_changed, this, control_ui));
+				mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::parameter_changed, this, control_ui), gui_context());
 				control_ui->pack_start(control_ui->label, true, true);
 				control_ui->pack_start(*control_ui->combo, false, true);
 
@@ -466,7 +466,7 @@ GenericPluginUI::build_control_ui (guint32 port_index, boost::shared_ptr<Automat
 			// control_ui->pack_start (control_ui->automate_button, false, false);
 
 			control_ui->button->signal_clicked().connect (sigc::bind (sigc::mem_fun(*this, &GenericPluginUI::control_port_toggled), control_ui));
-			mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::toggle_parameter_changed, this, control_ui));
+			mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::toggle_parameter_changed, this, control_ui), gui_context());
 
 			if (plugin->get_parameter (port_index) > 0.5){
 				control_ui->button->set_active(true);
@@ -542,8 +542,8 @@ GenericPluginUI::build_control_ui (guint32 port_index, boost::shared_ptr<Automat
 
 		automation_state_changed (control_ui);
 
-		mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::parameter_changed, this, control_ui));
-		mcontrol->alist()->automation_state_changed.connect (control_connections, boost::bind (&GenericPluginUI::automation_state_changed, this, control_ui));
+		mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::parameter_changed, this, control_ui), gui_context());
+		mcontrol->alist()->automation_state_changed.connect (control_connections, boost::bind (&GenericPluginUI::automation_state_changed, this, control_ui), gui_context());
 
 	} else if (plugin->parameter_is_output (port_index)) {
 
@@ -592,7 +592,7 @@ GenericPluginUI::build_control_ui (guint32 port_index, boost::shared_ptr<Automat
 		output_controls.push_back (control_ui);
 	}
 
-	mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::parameter_changed, this, control_ui));
+	mcontrol->Changed.connect (control_connections, boost::bind (&GenericPluginUI::parameter_changed, this, control_ui), gui_context());
 
 	return control_ui;
 }
diff --git a/gtk2_ardour/group_tabs.cc b/gtk2_ardour/group_tabs.cc
index 17cec93f82..8e7b8f0607 100644
--- a/gtk2_ardour/group_tabs.cc
+++ b/gtk2_ardour/group_tabs.cc
@@ -21,6 +21,8 @@
 #include "ardour/session.h"
 #include "ardour/route_group.h"
 #include "ardour/route.h"
+
+#include "gui_thread.h"
 #include "route_group_dialog.h"
 #include "group_tabs.h"
 #include "keyboard.h"
@@ -45,7 +47,7 @@ GroupTabs::set_session (Session* s)
 	EditorComponent::set_session (s);
 
 	if (_session) {
-		_session->RouteGroupChanged.connect (_session_connections, boost::bind (&GroupTabs::set_dirty, this));
+		_session->RouteGroupChanged.connect (_session_connections, boost::bind (&GroupTabs::set_dirty, this), gui_context());
 	}
 }
 
diff --git a/gtk2_ardour/gui_thread.h b/gtk2_ardour/gui_thread.h
index f932c603ac..edea9b9d21 100644
--- a/gtk2_ardour/gui_thread.h
+++ b/gtk2_ardour/gui_thread.h
@@ -22,6 +22,7 @@
 
 #include <gtkmm2ext/gtk_ui.h>
 #include <boost/bind.hpp>
+#include <boost/bind/protect.hpp>
 
 #define ENSURE_GUI_THREAD(obj,method, ...) \
      if (!Gtkmm2ext::UI::instance()->caller_is_self()) { \
@@ -29,4 +30,7 @@
         return;\
      }
 
+#define gui_context() Gtkmm2ext::UI::instance() /* a UICallback-derived object that specifies the event loop for GUI signal handling */
+#define ui_bind(f, ...) boost::protect (boost::bind (f, __VA_ARGS__))
+
 #endif /* __ardour_gtk_gui_thread_h__ */
diff --git a/gtk2_ardour/imageframe_time_axis.cc b/gtk2_ardour/imageframe_time_axis.cc
index 9dbcb31392..270dd01454 100644
--- a/gtk2_ardour/imageframe_time_axis.cc
+++ b/gtk2_ardour/imageframe_time_axis.cc
@@ -322,7 +322,7 @@ ImageFrameTimeAxis::add_marker_time_axis(MarkerTimeAxis* marker_track, void* src
 	else
 	{
 		marker_time_axis_list.push_back(marker_track) ;
-		marker_track->GoingAway.connect (*this, boost::bind (&ImageFrameTimeAxis::remove_time_axis_view, this, marker_track, (void*)this));
+		marker_track->GoingAway.connect (*this, boost::bind (&ImageFrameTimeAxis::remove_time_axis_view, this, marker_track, (void*)this), gui_context());
 
 		 MarkerTimeAxisAdded(marker_track, src) ; /* EMIT_SIGNAL */
 		ret = true ;
diff --git a/gtk2_ardour/imageframe_time_axis_group.cc b/gtk2_ardour/imageframe_time_axis_group.cc
index 4c33d73dfc..a555d5254b 100644
--- a/gtk2_ardour/imageframe_time_axis_group.cc
+++ b/gtk2_ardour/imageframe_time_axis_group.cc
@@ -216,7 +216,7 @@ ImageFrameTimeAxisGroup::add_imageframe_item(const string & frame_id, nframes_t
 
 		imageframe_views.push_front(ifv) ;
 
-		ifv->GoingAway.connect (*this, boost::bind (&ImageFrameTimeAxisGroup::remove_imageframe_item, this, (void*)this));
+		ifv->GoingAway.connect (*this, boost::bind (&ImageFrameTimeAxisGroup::remove_imageframe_item, this, (void*)this), gui_context());
 
 		 ImageFrameAdded(ifv, src) ; /* EMIT_SIGNAL */
 	}
diff --git a/gtk2_ardour/imageframe_time_axis_view.cc b/gtk2_ardour/imageframe_time_axis_view.cc
index 05dda6bc8e..5c00bc1e59 100644
--- a/gtk2_ardour/imageframe_time_axis_view.cc
+++ b/gtk2_ardour/imageframe_time_axis_view.cc
@@ -214,7 +214,7 @@ ImageFrameTimeAxisView::add_imageframe_group(std::string group_id, void* src)
 
 		imageframe_groups.push_front(iftag) ;
 
-		iftag->GoingAway.connect (*this, boost::bind (&ImageFrameTimeAxisView::remove_imageframe_group, this, iftag, (void*)this));
+		iftag->GoingAway.connect (*this, boost::bind (&ImageFrameTimeAxisView::remove_imageframe_group, this, iftag, (void*)this), gui_context());
 
 		ImageFrameGroupAdded(iftag, src) ; /* EMIT_SIGNAL */
 	}
diff --git a/gtk2_ardour/imageframe_view.cc b/gtk2_ardour/imageframe_view.cc
index 273ac30b99..1d8f5ceab7 100644
--- a/gtk2_ardour/imageframe_view.cc
+++ b/gtk2_ardour/imageframe_view.cc
@@ -287,7 +287,7 @@ ImageFrameView::add_marker_view_item(MarkerView* item, void* src)
 {
 	marker_view_list.push_back(item) ;
 
-	item->GoingAway.connect (*this, boost::bind (&ImageFrameView::remove_marker_view_item, this, (void*)this));
+	item->GoingAway.connect (*this, boost::bind (&ImageFrameView::remove_marker_view_item, this, (void*)this), gui_context());
 
 	 MarkerViewAdded(item, src) ; /* EMIT_SIGNAL */
 }
diff --git a/gtk2_ardour/io_selector.cc b/gtk2_ardour/io_selector.cc
index e038035a95..bc8f3b8890 100644
--- a/gtk2_ardour/io_selector.cc
+++ b/gtk2_ardour/io_selector.cc
@@ -272,7 +272,7 @@ PortInsertWindow::PortInsertWindow (ARDOUR::Session* sess, boost::shared_ptr<ARD
 
 	signal_delete_event().connect (sigc::mem_fun (*this, &PortInsertWindow::wm_delete), false);
 
-	pi->GoingAway.connect (going_away_connection, boost::bind (&PortInsertWindow::plugin_going_away, this));
+	pi->GoingAway.connect (going_away_connection, boost::bind (&PortInsertWindow::plugin_going_away, this), gui_context());
 }
 
 bool
diff --git a/gtk2_ardour/io_selector.h b/gtk2_ardour/io_selector.h
index 63e02a2a75..a4545dbfc4 100644
--- a/gtk2_ardour/io_selector.h
+++ b/gtk2_ardour/io_selector.h
@@ -122,7 +122,7 @@ class PortInsertWindow : public ArdourDialog
 	void accept ();
 
 	void plugin_going_away ();
-	boost::signals2::scoped_connection going_away_connection;
+	PBD::ScopedConnection going_away_connection;
 
 	bool wm_delete (GdkEventAny*);
 };
diff --git a/gtk2_ardour/level_meter.cc b/gtk2_ardour/level_meter.cc
index c0908d8295..679c5ac2b5 100644
--- a/gtk2_ardour/level_meter.cc
+++ b/gtk2_ardour/level_meter.cc
@@ -59,7 +59,7 @@ LevelMeter::LevelMeter (Session* s)
 {
 	set_session (s);
 	set_spacing (1);
-	Config->ParameterChanged.connect (_parameter_connection, boost::bind (&LevelMeter::parameter_changed, this, _1));
+	Config->ParameterChanged.connect (_parameter_connection, ui_bind (&LevelMeter::parameter_changed, this, _1), gui_context());
 	UI::instance()->theme_changed.connect (sigc::mem_fun(*this, &LevelMeter::on_theme_changed));
 	ColorsChanged.connect (sigc::mem_fun (*this, &LevelMeter::color_handler));
 	max_peak = minus_infinity();
@@ -85,7 +85,7 @@ LevelMeter::set_meter (PeakMeter* meter)
 	_meter = meter;
 
 	if (_meter) {
-		_meter->ConfigurationChanged.connect (_configuration_connection, boost::bind (&LevelMeter::configuration_changed, this, _1, _2));
+		_meter->ConfigurationChanged.connect (_configuration_connection, ui_bind (&LevelMeter::configuration_changed, this, _1, _2), gui_context());
 	}
 }
 
diff --git a/gtk2_ardour/location_ui.cc b/gtk2_ardour/location_ui.cc
index 61a0ec1405..439d64971b 100644
--- a/gtk2_ardour/location_ui.cc
+++ b/gtk2_ardour/location_ui.cc
@@ -282,11 +282,11 @@ LocationEditRow::set_location (Location *loc)
 	end_clock.set_sensitive (!location->locked());
 	length_clock.set_sensitive (!location->locked());
 
-	location->start_changed.connect (connections, boost::bind (&LocationEditRow::start_changed, this, _1));
-	location->end_changed.connect (connections, boost::bind (&LocationEditRow::end_changed, this, _1));
-	location->name_changed.connect (connections, boost::bind (&LocationEditRow::name_changed, this, _1));
-	location->changed.connect (connections, boost::bind (&LocationEditRow::location_changed, this, _1));
-	location->FlagsChanged.connect (connections, boost::bind (&LocationEditRow::flags_changed, this, _1, _2));
+	location->start_changed.connect (connections, ui_bind (&LocationEditRow::start_changed, this, _1), gui_context());
+	location->end_changed.connect (connections, ui_bind (&LocationEditRow::end_changed, this, _1), gui_context());
+	location->name_changed.connect (connections, ui_bind (&LocationEditRow::name_changed, this, _1), gui_context());
+	location->changed.connect (connections, ui_bind (&LocationEditRow::location_changed, this, _1), gui_context());
+	location->FlagsChanged.connect (connections, ui_bind (&LocationEditRow::flags_changed, this, _1, _2), gui_context());
 }
 
 void
@@ -860,10 +860,10 @@ LocationUI::set_session(ARDOUR::Session* s)
 	SessionHandlePtr::set_session (s);
 
 	if (_session) {
-		_session->locations()->changed.connect (_session_connections, boost::bind (&LocationUI::refresh_location_list, this));
-		_session->locations()->StateChanged.connect (_session_connections, boost::bind (&LocationUI::refresh_location_list, this));
-		_session->locations()->added.connect (_session_connections, boost::bind (&LocationUI::location_added, this, _1));
-		_session->locations()->removed.connect (_session_connections, boost::bind (&LocationUI::location_removed, this, _1));
+		_session->locations()->changed.connect (_session_connections, boost::bind (&LocationUI::refresh_location_list, this), gui_context());
+		_session->locations()->StateChanged.connect (_session_connections, boost::bind (&LocationUI::refresh_location_list, this), gui_context());
+		_session->locations()->added.connect (_session_connections, ui_bind (&LocationUI::location_added, this, _1), gui_context());
+		_session->locations()->removed.connect (_session_connections, ui_bind (&LocationUI::location_removed, this, _1), gui_context());
 	}
 
 	refresh_location_list ();
diff --git a/gtk2_ardour/lv2_plugin_ui.cc b/gtk2_ardour/lv2_plugin_ui.cc
index 2f108efc8a..d736ba723d 100644
--- a/gtk2_ardour/lv2_plugin_ui.cc
+++ b/gtk2_ardour/lv2_plugin_ui.cc
@@ -22,6 +22,7 @@
 #include "ardour/lv2_plugin.h"
 
 #include "ardour_ui.h"
+#include "gui_thread.h"
 #include "lv2_plugin_ui.h"
 
 using namespace Gtk;
@@ -227,7 +228,7 @@ LV2PluginUI::lv2ui_instantiate(const Glib::ustring& title)
 		}
 	}
 
-	_lv2->ParameterChanged.connect (parameter_connection, boost::bind (&LV2PluginUI::parameter_changed, this, _1, _2));
+	_lv2->ParameterChanged.connect (parameter_connection, ui_bind (&LV2PluginUI::parameter_changed, this, _1, _2), gui_context());
 }
 
 LV2PluginUI::~LV2PluginUI ()
diff --git a/gtk2_ardour/marker_time_axis_view.cc b/gtk2_ardour/marker_time_axis_view.cc
index 2d9a30b0a3..6e955146a2 100644
--- a/gtk2_ardour/marker_time_axis_view.cc
+++ b/gtk2_ardour/marker_time_axis_view.cc
@@ -211,7 +211,7 @@ MarkerTimeAxisView::add_marker_view(ImageFrameView* ifv, std::string mark_type,
 	ifv->add_marker_view_item(mv, src) ;
 	marker_view_list.push_front(mv) ;
 
-	mv->GoingAway.connect (*this, boost::bind (&MarkerTimeAxisView::remove_marker_view, this, (void*)this));
+	mv->GoingAway.connect (*this, boost::bind (&MarkerTimeAxisView::remove_marker_view, this, (void*)this), gui_context());
 
 	 MarkerViewAdded(mv,src) ; /* EMIT_SIGNAL */
 
diff --git a/gtk2_ardour/midi_region_view.cc b/gtk2_ardour/midi_region_view.cc
index 4f0c25a72c..8d186eac9b 100644
--- a/gtk2_ardour/midi_region_view.cc
+++ b/gtk2_ardour/midi_region_view.cc
@@ -585,7 +585,7 @@ MidiRegionView::display_model(boost::shared_ptr<MidiModel> model)
 {
 	_model = model;
 	content_connection.disconnect ();
-	_model->ContentsChanged.connect (content_connection, boost::bind (&MidiRegionView::redisplay_model, this));
+	_model->ContentsChanged.connect (content_connection, boost::bind (&MidiRegionView::redisplay_model, this), gui_context());
 
 	clear_events ();
 
@@ -1071,7 +1071,7 @@ MidiRegionView::add_ghost (TimeAxisView& tv)
 		}
 	}
 
-	ghost->GoingAway.connect (*this, boost::bind (&RegionView::remove_ghost, this, _1));
+	ghost->GoingAway.connect (*this, ui_bind (&RegionView::remove_ghost, this, _1), gui_context());
 
 	return ghost;
 }
diff --git a/gtk2_ardour/midi_region_view.h b/gtk2_ardour/midi_region_view.h
index e8c25e8647..66f0393f3d 100644
--- a/gtk2_ardour/midi_region_view.h
+++ b/gtk2_ardour/midi_region_view.h
@@ -25,7 +25,7 @@
 #include <libgnomecanvasmm.h>
 #include <libgnomecanvasmm/polygon.h>
 
-#include <boost/signals2.hpp>
+#include "pbd/signals.h"
 
 #include "ardour/midi_track.h"
 #include "ardour/midi_region.h"
@@ -389,7 +389,7 @@ class MidiRegionView : public RegionView
 	std::vector<NoteResizeData *> _resize_data;
 
 	/* connection used to connect to model's ContentChanged signal */
-	boost::signals2::scoped_connection content_connection;
+	PBD::ScopedConnection content_connection;
 
 	ArdourCanvas::CanvasNoteEvent* find_canvas_note (boost::shared_ptr<NoteType>);
 	Events::iterator _optimization_iterator;
diff --git a/gtk2_ardour/midi_streamview.cc b/gtk2_ardour/midi_streamview.cc
index 76d34a4a50..0d50c8910f 100644
--- a/gtk2_ardour/midi_streamview.cc
+++ b/gtk2_ardour/midi_streamview.cc
@@ -180,7 +180,7 @@ MidiStreamView::add_region_view_internal (boost::shared_ptr<Region> r, bool wfd,
 	display_region (region_view, wfd);
 
 	/* catch regionview going away */
-	region->GoingAway.connect (*this, boost::bind (&MidiStreamView::remove_region_view, this, region));
+	region->GoingAway.connect (*this, boost::bind (&MidiStreamView::remove_region_view, this, region), gui_context());
 
 	RegionViewAdded (region_view);
 
@@ -402,8 +402,9 @@ MidiStreamView::setup_rec_box ()
 				sources.push_back(mds->write_source());
 
 				mds->write_source()->ViewDataRangeReady.connect 
-					(rec_data_ready_connections, boost::bind (&MidiStreamView::rec_data_range_ready, this,
-										  _1, _2, boost::weak_ptr<Source>(mds->write_source())));
+					(rec_data_ready_connections, 
+					 ui_bind (&MidiStreamView::rec_data_range_ready, this, _1, _2, boost::weak_ptr<Source>(mds->write_source())),
+					 gui_context());
 
 				// handle multi
 
diff --git a/gtk2_ardour/midi_time_axis.cc b/gtk2_ardour/midi_time_axis.cc
index 3b1ad17a22..3b759867c8 100644
--- a/gtk2_ardour/midi_time_axis.cc
+++ b/gtk2_ardour/midi_time_axis.cc
@@ -137,7 +137,7 @@ MidiTimeAxisView::MidiTimeAxisView (PublicEditor& ed, Session* sess,
 
 	set_state (*xml_node, Stateful::loading_state_version);
 
-	_route->processors_changed.connect (*this, boost::bind (&MidiTimeAxisView::processors_changed, this, _1));
+	_route->processors_changed.connect (*this, ui_bind (&MidiTimeAxisView::processors_changed, this, _1), gui_context());
 
 	if (is_track()) {
 		_piano_roll_header = new PianoRollHeader(*midi_view());
diff --git a/gtk2_ardour/mixer_strip.cc b/gtk2_ardour/mixer_strip.cc
index 275cd14b02..9578e8dd0c 100644
--- a/gtk2_ardour/mixer_strip.cc
+++ b/gtk2_ardour/mixer_strip.cc
@@ -257,8 +257,8 @@ MixerStrip::init ()
 	_packed = false;
 	_embedded = false;
 
-	_session->engine().Stopped.connect (*this, boost::bind (&MixerStrip::engine_stopped, this));
-	_session->engine().Running.connect (*this, boost::bind (&MixerStrip::engine_running, this));
+	_session->engine().Stopped.connect (*this, boost::bind (&MixerStrip::engine_stopped, this), gui_context());
+	_session->engine().Running.connect (*this, boost::bind (&MixerStrip::engine_running, this), gui_context());
 
 	input_button.signal_button_press_event().connect (sigc::mem_fun(*this, &MixerStrip::input_press), false);
 	output_button.signal_button_press_event().connect (sigc::mem_fun(*this, &MixerStrip::output_press), false);
@@ -363,7 +363,7 @@ MixerStrip::set_route (boost::shared_ptr<Route> rt)
 
 		boost::shared_ptr<AudioTrack> at = audio_track();
 
-		at->FreezeChange.connect (route_connections, boost::bind (&MixerStrip::map_frozen, this));
+		at->FreezeChange.connect (route_connections, boost::bind (&MixerStrip::map_frozen, this), gui_context());
 
 		button_table.attach (*rec_enable_button, 0, 2, 2, 3);
 		rec_enable_button->set_sensitive (_session->writable());
@@ -412,22 +412,22 @@ MixerStrip::set_route (boost::shared_ptr<Route> rt)
 						   _("Click to Add/Edit Comments"):
 						   _route->comment());
 
-	_route->meter_change.connect (route_connections, boost::bind (&MixerStrip::meter_changed, this, _1));
-	_route->input()->changed.connect (route_connections, boost::bind (&MixerStrip::input_changed, this, _1, _2));
-	_route->output()->changed.connect (route_connections, boost::bind (&MixerStrip::output_changed, this, _1, _2));
-	_route->route_group_changed.connect (route_connections, boost::bind (&MixerStrip::route_group_changed, this));
+	_route->meter_change.connect (route_connections, ui_bind (&MixerStrip::meter_changed, this, _1), gui_context());
+	_route->input()->changed.connect (route_connections, ui_bind (&MixerStrip::input_changed, this, _1, _2), gui_context());
+	_route->output()->changed.connect (route_connections, ui_bind (&MixerStrip::output_changed, this, _1, _2), gui_context());
+	_route->route_group_changed.connect (route_connections, boost::bind (&MixerStrip::route_group_changed, this), gui_context());
 
 	if (_route->panner()) {
-		_route->panner()->Changed.connect (route_connections, boost::bind (&MixerStrip::connect_to_pan, this));
+		_route->panner()->Changed.connect (route_connections, boost::bind (&MixerStrip::connect_to_pan, this), gui_context());
 	}
 
 	if (is_audio_track()) {
-		audio_track()->DiskstreamChanged.connect (route_connections, boost::bind (&MixerStrip::diskstream_changed, this));
+		audio_track()->DiskstreamChanged.connect (route_connections, boost::bind (&MixerStrip::diskstream_changed, this), gui_context());
 	}
 
-	_route->NameChanged.connect (route_connections, boost::bind (&RouteUI::name_changed, this));
-	_route->comment_changed.connect (route_connections, boost::bind (&MixerStrip::comment_changed, this, _1));
-	_route->gui_changed.connect (route_connections, boost::bind (&MixerStrip::route_gui_changed, this, _1, _2));
+	_route->NameChanged.connect (route_connections, boost::bind (&RouteUI::name_changed, this), gui_context());
+	_route->comment_changed.connect (route_connections, ui_bind (&MixerStrip::comment_changed, this, _1), gui_context());
+	_route->gui_changed.connect (route_connections, ui_bind (&MixerStrip::route_gui_changed, this, _1, _2), gui_context());
 
 	set_stuff_from_route ();
 
@@ -928,8 +928,8 @@ MixerStrip::connect_to_pan ()
 				_route->panner()->data().control(Evoral::Parameter(PanAutomation)));
 
 	if (pan_control) {
-		pan_control->alist()->automation_state_changed.connect (panstate_connection, boost::bind (&PannerUI::pan_automation_state_changed, &panners));
-		pan_control->alist()->automation_style_changed.connect (panstyle_connection, boost::bind (&PannerUI::pan_automation_style_changed, &panners));
+		pan_control->alist()->automation_state_changed.connect (panstate_connection, boost::bind (&PannerUI::pan_automation_state_changed, &panners), gui_context());
+		pan_control->alist()->automation_style_changed.connect (panstyle_connection, boost::bind (&PannerUI::pan_automation_style_changed, &panners), gui_context());
 	}
 
 	panners.pan_changed (this);
@@ -1693,7 +1693,7 @@ MixerStrip::show_send (boost::shared_ptr<Send> send)
 	_current_delivery = send;
 
 	send->set_metering (true);
-	_current_delivery->GoingAway.connect (send_gone_connection, boost::bind (&MixerStrip::revert_to_default_display, this));
+	_current_delivery->GoingAway.connect (send_gone_connection, boost::bind (&MixerStrip::revert_to_default_display, this), gui_context());
 
 	gain_meter().set_controls (_route, send->meter(), send->amp());
 	gain_meter().setup_meters ();
diff --git a/gtk2_ardour/mixer_strip.h b/gtk2_ardour/mixer_strip.h
index 64579e0c33..0e432eed3e 100644
--- a/gtk2_ardour/mixer_strip.h
+++ b/gtk2_ardour/mixer_strip.h
@@ -214,8 +214,8 @@ class MixerStrip : public RouteUI, public Gtk::EventBox
 	void input_changed (ARDOUR::IOChange, void *);
 	void output_changed (ARDOUR::IOChange, void *);
 
-	boost::signals2::scoped_connection panstate_connection;
-	boost::signals2::scoped_connection panstyle_connection;
+	PBD::ScopedConnection panstate_connection;
+	PBD::ScopedConnection panstyle_connection;
 	void connect_to_pan ();
 
 	void update_diskstream_display ();
@@ -265,7 +265,7 @@ class MixerStrip : public RouteUI, public Gtk::EventBox
 	void revert_to_default_display ();
 
 	void drop_send ();
-	boost::signals2::scoped_connection send_gone_connection;
+	PBD::ScopedConnection send_gone_connection;
 
 	void reset_strip_style ();
 
diff --git a/gtk2_ardour/mixer_ui.cc b/gtk2_ardour/mixer_ui.cc
index 0484db6fe7..799352c87d 100644
--- a/gtk2_ardour/mixer_ui.cc
+++ b/gtk2_ardour/mixer_ui.cc
@@ -74,7 +74,7 @@ Mixer_UI::Mixer_UI ()
 	strip_redisplay_does_not_sync_order_keys = false;
 	ignore_sync = false;
 
-	Route::SyncOrderKeys.connect (*this, boost::bind (&Mixer_UI::sync_order_keys, this, _1));
+	Route::SyncOrderKeys.connect (*this, ui_bind (&Mixer_UI::sync_order_keys, this, _1), gui_context());
 
 	scroller_base.add_events (Gdk::BUTTON_PRESS_MASK|Gdk::BUTTON_RELEASE_MASK);
 	scroller_base.set_name ("MixerWindow");
@@ -333,9 +333,9 @@ Mixer_UI::add_strip (RouteList& routes)
 			route->set_order_key (N_("signal"), track_model->children().size()-1);
 		}
 
-		route->NameChanged.connect (*this,  boost::bind (&Mixer_UI::strip_name_changed, this, strip));
+		route->NameChanged.connect (*this, boost::bind (&Mixer_UI::strip_name_changed, this, strip), gui_context());
 
-		strip->GoingAway.connect (*this, boost::bind (&Mixer_UI::remove_strip, this, strip));
+		strip->GoingAway.connect (*this, boost::bind (&Mixer_UI::remove_strip, this, strip), gui_context());
 		strip->WidthChanged.connect (sigc::mem_fun(*this, &Mixer_UI::strip_width_changed));
 		strip->signal_button_release_event().connect (sigc::bind (sigc::mem_fun(*this, &Mixer_UI::strip_button_release_event), strip));
 	}
@@ -476,10 +476,10 @@ Mixer_UI::set_session (Session* sess)
 
 	initial_track_display ();
 
-	_session->RouteAdded.connect (_session_connections, boost::bind (&Mixer_UI::add_strip, this, _1));
-	_session->route_group_added.connect (_session_connections, boost::bind (&Mixer_UI::add_route_group, this, _1));
-	_session->route_group_removed.connect (_session_connections, boost::bind (&Mixer_UI::route_groups_changed, this));
-	_session->config.ParameterChanged.connect (_session_connections, boost::bind (&Mixer_UI::parameter_changed, this, _1));
+	_session->RouteAdded.connect (_session_connections, ui_bind (&Mixer_UI::add_strip, this, _1), gui_context());
+	_session->route_group_added.connect (_session_connections, ui_bind (&Mixer_UI::add_route_group, this, _1), gui_context());
+	_session->route_group_removed.connect (_session_connections, boost::bind (&Mixer_UI::route_groups_changed, this), gui_context());
+	_session->config.ParameterChanged.connect (_session_connections, ui_bind (&Mixer_UI::parameter_changed, this, _1), gui_context());
 
 	route_groups_changed ();
 
@@ -1252,7 +1252,7 @@ Mixer_UI::add_route_group (RouteGroup* group)
 		focus = true;
 	}
 
-	group->FlagsChanged.connect (*this,  boost::bind (&Mixer_UI::group_flags_changed, this, _1, group));
+	group->FlagsChanged.connect (*this, ui_bind (&Mixer_UI::group_flags_changed, this, _1, group), gui_context());
 
 	if (focus) {
 		TreeViewColumn* col = group_display.get_column (0);
diff --git a/gtk2_ardour/option_editor.cc b/gtk2_ardour/option_editor.cc
index f11731b6de..b779d24421 100644
--- a/gtk2_ardour/option_editor.cc
+++ b/gtk2_ardour/option_editor.cc
@@ -164,7 +164,7 @@ OptionEditor::OptionEditor (Configuration* c, std::string const & t)
 	show_all_children();
 
 	/* Watch out for changes to parameters */
-	_config->ParameterChanged.connect (config_connection, boost::bind (&OptionEditor::parameter_changed, this, _1));
+	_config->ParameterChanged.connect (config_connection, ui_bind (&OptionEditor::parameter_changed, this, _1), gui_context());
 }
 
 OptionEditor::~OptionEditor ()
diff --git a/gtk2_ardour/panner2d.cc b/gtk2_ardour/panner2d.cc
index 8b7f5802b5..3e70472ffe 100644
--- a/gtk2_ardour/panner2d.cc
+++ b/gtk2_ardour/panner2d.cc
@@ -72,8 +72,8 @@ Panner2d::Panner2d (boost::shared_ptr<Panner> p, int32_t h)
 	allow_y = false;
 	allow_target = false;
 
-	panner->StateChanged.connect (state_connection, boost::bind (&Panner2d::handle_state_change, this));
-	panner->Changed.connect (change_connection, boost::bind (&Panner2d::handle_position_change, this));
+	panner->StateChanged.connect (state_connection, boost::bind (&Panner2d::handle_state_change, this), gui_context());
+	panner->Changed.connect (change_connection, boost::bind (&Panner2d::handle_position_change, this), gui_context());
 
 	drag_target = 0;
 	set_events (Gdk::BUTTON_PRESS_MASK|Gdk::BUTTON_RELEASE_MASK|Gdk::POINTER_MOTION_MASK);
diff --git a/gtk2_ardour/panner_ui.cc b/gtk2_ardour/panner_ui.cc
index 4321a7ebad..0d2297383c 100644
--- a/gtk2_ardour/panner_ui.cc
+++ b/gtk2_ardour/panner_ui.cc
@@ -151,9 +151,9 @@ PannerUI::set_panner (boost::shared_ptr<Panner> p)
 		return;
 	}
 
-	_panner->Changed.connect (connections, boost::bind (&PannerUI::panner_changed, this));
-	_panner->LinkStateChanged.connect (connections, boost::bind (&PannerUI::update_pan_linkage, this));
-	_panner->StateChanged.connect (connections, boost::bind (&PannerUI::update_pan_state, this));
+	_panner->Changed.connect (connections, boost::bind (&PannerUI::panner_changed, this), gui_context());
+	_panner->LinkStateChanged.connect (connections, boost::bind (&PannerUI::update_pan_linkage, this), gui_context());
+	_panner->StateChanged.connect (connections, boost::bind (&PannerUI::update_pan_state, this), gui_context());
 
 	setup_pan ();
 
@@ -404,7 +404,7 @@ PannerUI::setup_pan ()
 			pan_adjustments.back()->set_value(rx);
 			pan_adjustments.back()->signal_value_changed().connect (sigc::bind (sigc::mem_fun(*this, &PannerUI::pan_adjustment_changed), (uint32_t) asz));
 
-			_panner->pan_control( asz )->Changed.connect (connections, boost::bind (&PannerUI::pan_value_changed, this, (uint32_t) asz));
+			_panner->pan_control( asz )->Changed.connect (connections, boost::bind (&PannerUI::pan_value_changed, this, (uint32_t) asz), gui_context());
 
 			bc->set_name ("PanSlider");
 			bc->set_shadow_type (Gtk::SHADOW_NONE);
diff --git a/gtk2_ardour/plugin_eq_gui.cc b/gtk2_ardour/plugin_eq_gui.cc
index 3ee64fc9b5..9ec485b62b 100644
--- a/gtk2_ardour/plugin_eq_gui.cc
+++ b/gtk2_ardour/plugin_eq_gui.cc
@@ -115,7 +115,7 @@ PluginEqGui::PluginEqGui(boost::shared_ptr<ARDOUR::PluginInsert> pluginInsert)
 
 
 	// Connect the realtime signal collection callback
-	_plugin_insert->AnalysisDataGathered.connect (analysis_connection, boost::bind (&PluginEqGui::signal_collect_callback, this, _1, _2));
+	_plugin_insert->AnalysisDataGathered.connect (analysis_connection, ui_bind (&PluginEqGui::signal_collect_callback, this, _1, _2), gui_context());
 }
 
 PluginEqGui::~PluginEqGui()
diff --git a/gtk2_ardour/plugin_selector.cc b/gtk2_ardour/plugin_selector.cc
index 48bb5f5c7e..63ec9abf37 100644
--- a/gtk2_ardour/plugin_selector.cc
+++ b/gtk2_ardour/plugin_selector.cc
@@ -74,7 +74,7 @@ PluginSelector::PluginSelector (PluginManager *mgr)
 	manager = mgr;
 	in_row_change = false;
 
-	manager->PluginListChanged.connect (plugin_list_changed_connection, boost::bind (&PluginSelector::build_plugin_menu, this));
+	manager->PluginListChanged.connect (plugin_list_changed_connection, boost::bind (&PluginSelector::build_plugin_menu, this), gui_context());
 	build_plugin_menu ();
 
 	plugin_model = Gtk::ListStore::create (plugin_columns);
diff --git a/gtk2_ardour/plugin_ui.cc b/gtk2_ardour/plugin_ui.cc
index 24106c4351..209904dea1 100644
--- a/gtk2_ardour/plugin_ui.cc
+++ b/gtk2_ardour/plugin_ui.cc
@@ -142,7 +142,7 @@ PluginUIWindow::PluginUIWindow (Gtk::Window* win, boost::shared_ptr<PluginInsert
 	add_events (Gdk::KEY_PRESS_MASK|Gdk::KEY_RELEASE_MASK|Gdk::BUTTON_PRESS_MASK|Gdk::BUTTON_RELEASE_MASK);
 
 	signal_delete_event().connect (sigc::bind (sigc::ptr_fun (just_hide_it), reinterpret_cast<Window*> (this)), false);
-	insert->GoingAway.connect (death_connection, boost::bind (&PluginUIWindow::plugin_going_away, this));
+	insert->GoingAway.connect (death_connection, boost::bind (&PluginUIWindow::plugin_going_away, this), gui_context());
 
 	gint h = _pluginui->get_preferred_height ();
 	gint w = _pluginui->get_preferred_width ();
@@ -390,7 +390,7 @@ PlugUIBase::PlugUIBase (boost::shared_ptr<PluginInsert> pi)
 	save_button.set_name ("PluginSaveButton");
 	save_button.signal_clicked().connect(sigc::mem_fun(*this, &PlugUIBase::save_plugin_setting));
 
-	insert->ActiveChanged.connect (active_connection, boost::bind (&PlugUIBase::processor_active_changed, this,  boost::weak_ptr<Processor>(insert)));
+	insert->ActiveChanged.connect (active_connection, boost::bind (&PlugUIBase::processor_active_changed, this,  boost::weak_ptr<Processor>(insert)), gui_context());
 
 	bypass_button.set_active (!pi->active());
 
@@ -414,7 +414,7 @@ PlugUIBase::PlugUIBase (boost::shared_ptr<PluginInsert> pi)
 	plugin_analysis_expander.property_expanded().signal_changed().connect( sigc::mem_fun(*this, &PlugUIBase::toggle_plugin_analysis));
 	plugin_analysis_expander.set_expanded(false);
 	
-	insert->GoingAway.connect (death_connection, boost::bind (&PlugUIBase::plugin_going_away, this));
+	insert->GoingAway.connect (death_connection, boost::bind (&PlugUIBase::plugin_going_away, this), gui_context());
 }
 
 PlugUIBase::~PlugUIBase()
diff --git a/gtk2_ardour/plugin_ui.h b/gtk2_ardour/plugin_ui.h
index b2e0504538..d1ea82f830 100644
--- a/gtk2_ardour/plugin_ui.h
+++ b/gtk2_ardour/plugin_ui.h
@@ -264,7 +264,7 @@ class PluginUIWindow : public Gtk::Window
   private:
 	Glib::ustring _title;
 	PlugUIBase* _pluginui;
-	boost::signals2::scoped_connection death_connection;
+	PBD::ScopedConnection death_connection;
 	Gtk::Window* parent;
 	Gtk::VBox vbox;
 	bool non_gtk_gui;
diff --git a/gtk2_ardour/port_group.cc b/gtk2_ardour/port_group.cc
index 4c983d1a62..3b10ff1abf 100644
--- a/gtk2_ardour/port_group.cc
+++ b/gtk2_ardour/port_group.cc
@@ -30,6 +30,7 @@
 #include "ardour/session.h"
 #include "ardour/auditioner.h"
 
+#include "gui_thread.h"
 #include "port_group.h"
 #include "port_matrix.h"
 #include "time_axis_view.h"
@@ -116,7 +117,7 @@ PortGroup::add_bundle_internal (boost::shared_ptr<Bundle> b, boost::shared_ptr<I
 	}
 
 	BundleRecord* br = new BundleRecord (b, io, colour, has_colour);
-	b->Changed.connect (br->changed_connection, boost::bind (&PortGroup::bundle_changed, this, _1));
+	b->Changed.connect (br->changed_connection, ui_bind (&PortGroup::bundle_changed, this, _1), gui_context());
 	_bundles.push_back (br);
 
 	Changed ();	
@@ -521,8 +522,8 @@ PortGroupList::add_group (boost::shared_ptr<PortGroup> g)
 {
 	_groups.push_back (g);
 
-	g->Changed.connect (_changed_connections, boost::bind (&PortGroupList::emit_changed, this));
-	g->BundleChanged.connect (_bundle_changed_connections, boost::bind (&PortGroupList::emit_bundle_changed, this, _1));
+	g->Changed.connect (_changed_connections, boost::bind (&PortGroupList::emit_changed, this), gui_context());
+	g->BundleChanged.connect (_bundle_changed_connections, ui_bind (&PortGroupList::emit_bundle_changed, this, _1), gui_context());
 
 	emit_changed ();
 }
diff --git a/gtk2_ardour/port_group.h b/gtk2_ardour/port_group.h
index bc0615a7a9..d5868bddd6 100644
--- a/gtk2_ardour/port_group.h
+++ b/gtk2_ardour/port_group.h
@@ -78,7 +78,7 @@ public:
 	    boost::shared_ptr<ARDOUR::IO> io; 
 	    Gdk::Color colour;
 	    bool has_colour;
-	    boost::signals2::scoped_connection changed_connection;
+	    PBD::ScopedConnection changed_connection;
 
 	    BundleRecord (boost::shared_ptr<ARDOUR::Bundle>, boost::shared_ptr<ARDOUR::IO>, Gdk::Color, bool has_colour);
 	};
diff --git a/gtk2_ardour/port_matrix.cc b/gtk2_ardour/port_matrix.cc
index 7e2a1d892a..33115432e6 100644
--- a/gtk2_ardour/port_matrix.cc
+++ b/gtk2_ardour/port_matrix.cc
@@ -135,10 +135,10 @@ PortMatrix::init ()
 
 	for (int i = 0; i < 2; ++i) {
 		/* watch for the content of _ports[] changing */
-		_ports[i].Changed.connect (_changed_connections, boost::bind (&PortMatrix::setup, this));
+		_ports[i].Changed.connect (_changed_connections, boost::bind (&PortMatrix::setup, this), gui_context());
 
 		/* and for bundles in _ports[] changing */
-		_ports[i].BundleChanged.connect (_bundle_changed_connections,  boost::bind (&PortMatrix::setup, this));
+		_ports[i].BundleChanged.connect (_bundle_changed_connections, boost::bind (&PortMatrix::setup, this), gui_context());
 	}
 
 	/* scrolling stuff */
@@ -149,13 +149,13 @@ PortMatrix::init ()
 	/* Part 2: notice when things have changed that require our subclass to clear and refill _ports[] */
 	
 	/* watch for routes being added or removed */
-	_session->RouteAdded.connect (_session_connections, boost::bind (&PortMatrix::routes_changed, this));
+	_session->RouteAdded.connect (_session_connections, boost::bind (&PortMatrix::routes_changed, this), gui_context());
 
 	/* and also bundles */
-	_session->BundleAdded.connect (_session_connections, boost::bind (&PortMatrix::setup_global_ports, this));
+	_session->BundleAdded.connect (_session_connections, boost::bind (&PortMatrix::setup_global_ports, this), gui_context());
 
 	/* and also ports */
-	_session->engine().PortRegisteredOrUnregistered.connect (_session_connections, boost::bind (&PortMatrix::setup_global_ports, this));
+	_session->engine().PortRegisteredOrUnregistered.connect (_session_connections, boost::bind (&PortMatrix::setup_global_ports, this), gui_context());
 
 	reconnect_to_routes ();
 	
@@ -170,7 +170,7 @@ PortMatrix::reconnect_to_routes ()
 
 	boost::shared_ptr<RouteList> routes = _session->get_routes ();
 	for (RouteList::iterator i = routes->begin(); i != routes->end(); ++i) {
-		(*i)->processors_changed.connect (_route_connections, boost::bind (&PortMatrix::route_processors_changed, this, _1));
+		(*i)->processors_changed.connect (_route_connections, ui_bind (&PortMatrix::route_processors_changed, this, _1), gui_context());
 	}
 }
 
diff --git a/gtk2_ardour/port_matrix_body.cc b/gtk2_ardour/port_matrix_body.cc
index 0732873f5c..e14a16d180 100644
--- a/gtk2_ardour/port_matrix_body.cc
+++ b/gtk2_ardour/port_matrix_body.cc
@@ -20,6 +20,8 @@
 #include <iostream>
 #include "ardour/bundle.h"
 #include "ardour/types.h"
+
+#include "gui_thread.h"
 #include "port_matrix_body.h"
 #include "port_matrix.h"
 #include "port_matrix_column_labels.h"
@@ -254,7 +256,7 @@ PortMatrixBody::setup ()
 		PortGroup::BundleList r = _matrix->visible_rows()->bundles ();
 		for (PortGroup::BundleList::iterator i = r.begin(); i != r.end(); ++i) {
 			
-			(*i)->bundle->Changed.connect (_bundle_connections, boost::bind (&PortMatrixBody::rebuild_and_draw_row_labels, this));
+			(*i)->bundle->Changed.connect (_bundle_connections, boost::bind (&PortMatrixBody::rebuild_and_draw_row_labels, this), gui_context());
 			
 		}
 	}
@@ -262,7 +264,7 @@ PortMatrixBody::setup ()
 	if (_matrix->visible_columns()) {
 		PortGroup::BundleList c = _matrix->visible_columns()->bundles ();
 		for (PortGroup::BundleList::iterator i = c.begin(); i != c.end(); ++i) {
-			(*i)->bundle->Changed.connect (_bundle_connections, boost::bind (&PortMatrixBody::rebuild_and_draw_column_labels, this));
+			(*i)->bundle->Changed.connect (_bundle_connections, boost::bind (&PortMatrixBody::rebuild_and_draw_column_labels, this), gui_context());
 		}
 	}
 		
diff --git a/gtk2_ardour/processor_box.cc b/gtk2_ardour/processor_box.cc
index 615294b6ac..400063c2b6 100644
--- a/gtk2_ardour/processor_box.cc
+++ b/gtk2_ardour/processor_box.cc
@@ -106,8 +106,8 @@ ProcessorEntry::ProcessorEntry (boost::shared_ptr<Processor> p, Width w)
 	_active.set_active (_processor->active ());
 	_active.signal_toggled().connect (sigc::mem_fun (*this, &ProcessorEntry::active_toggled));
 	
-	_processor->ActiveChanged.connect (active_connection, boost::bind (&ProcessorEntry::processor_active_changed, this));
-	_processor->NameChanged.connect (name_connection, boost::bind (&ProcessorEntry::processor_name_changed, this));
+	_processor->ActiveChanged.connect (active_connection, boost::bind (&ProcessorEntry::processor_active_changed, this), gui_context());
+	_processor->NameChanged.connect (name_connection, boost::bind (&ProcessorEntry::processor_name_changed, this), gui_context());
 }
 
 EventBox&
@@ -229,7 +229,7 @@ SendProcessorEntry::SendProcessorEntry (boost::shared_ptr<Send> s, Width w)
 	_vbox.pack_start (_fader);
 
 	_adjustment.signal_value_changed().connect (sigc::mem_fun (*this, &SendProcessorEntry::gain_adjusted));
-	_send->amp()->gain_control()->Changed.connect (send_gain_connection, boost::bind (&SendProcessorEntry::show_gain, this));
+	_send->amp()->gain_control()->Changed.connect (send_gain_connection, boost::bind (&SendProcessorEntry::show_gain, this), gui_context());
 	show_gain ();
 }
 
@@ -326,9 +326,9 @@ ProcessorBox::set_route (boost::shared_ptr<Route> r)
 	no_processor_redisplay = false;
 	_route = r;
 
-	_route->processors_changed.connect (connections, boost::bind (&ProcessorBox::route_processors_changed, this, _1));
-	_route->GoingAway.connect (connections, boost::bind (&ProcessorBox::route_going_away, this));
-	_route->NameChanged.connect (connections, boost::bind (&ProcessorBox::route_name_changed, this));
+	_route->processors_changed.connect (connections, ui_bind (&ProcessorBox::route_processors_changed, this, _1), gui_context());
+	_route->GoingAway.connect (connections, boost::bind (&ProcessorBox::route_going_away, this), gui_context());
+	_route->NameChanged.connect (connections, boost::bind (&ProcessorBox::route_name_changed, this), gui_context());
 
 	redisplay_processors ();
 }
diff --git a/gtk2_ardour/rc_option_editor.cc b/gtk2_ardour/rc_option_editor.cc
index c4c75ea6d7..4a5bce4674 100644
--- a/gtk2_ardour/rc_option_editor.cc
+++ b/gtk2_ardour/rc_option_editor.cc
@@ -10,6 +10,8 @@
 #include "ardour/rc_configuration.h"
 #include "ardour/control_protocol_manager.h"
 #include "control_protocol/control_protocol.h"
+
+#include "gui_thread.h"
 #include "rc_option_editor.h"
 #include "utils.h"
 #include "midi_port_dialog.h"
@@ -117,7 +119,7 @@ private:
 
 			if ((*i)->input()) {
 				r[_model.online] = !(*i)->input()->offline();
-				(*i)->input()->OfflineStatusChanged.connect (port_connections, boost::bind (&MIDIPorts::port_offline_changed, this, (*i)));
+				(*i)->input()->OfflineStatusChanged.connect (port_connections, boost::bind (&MIDIPorts::port_offline_changed, this, (*i)), gui_context());
 				r[_model.trace_input] = (*i)->input()->tracing();
 			}
 
diff --git a/gtk2_ardour/region_selection.cc b/gtk2_ardour/region_selection.cc
index bbb5d33865..637d902ff7 100644
--- a/gtk2_ardour/region_selection.cc
+++ b/gtk2_ardour/region_selection.cc
@@ -20,6 +20,7 @@
 
 #include "ardour/region.h"
 
+#include "gui_thread.h"
 #include "region_view.h"
 #include "region_selection.h"
 #include "time_axis_view.h"
@@ -32,7 +33,7 @@ using namespace PBD;
  */
 RegionSelection::RegionSelection ()
 {
-	RegionView::RegionViewGoingAway.connect (death_connection, boost::bind (&RegionSelection::remove_it, this, _1));
+	RegionView::RegionViewGoingAway.connect (death_connection, ui_bind (&RegionSelection::remove_it, this, _1), gui_context());
 
 	_current_start = 0;
 	_current_end = 0;
@@ -44,7 +45,7 @@ RegionSelection::RegionSelection ()
 RegionSelection::RegionSelection (const RegionSelection& other)
 	: std::list<RegionView*>()
 {
-	RegionView::RegionViewGoingAway.connect (death_connection, boost::bind (&RegionSelection::remove_it, this, _1));
+	RegionView::RegionViewGoingAway.connect (death_connection, ui_bind (&RegionSelection::remove_it, this, _1), gui_context());
 
 	_current_start = other._current_start;
 	_current_end = other._current_end;
diff --git a/gtk2_ardour/region_selection.h b/gtk2_ardour/region_selection.h
index dcb6d68e0c..c4ad44da37 100644
--- a/gtk2_ardour/region_selection.h
+++ b/gtk2_ardour/region_selection.h
@@ -22,8 +22,7 @@
 #include <set>
 #include <list>
 
-#include <boost/signals2.hpp>
-
+#include "pbd/signals.h"
 #include "ardour/types.h"
 
 class RegionView;
@@ -71,7 +70,7 @@ class RegionSelection : public std::list<RegionView*>
 	nframes_t _current_end; ///< end position for the selection
 
 	std::list<RegionView *> _bylayer; ///< list of regions sorted by layer
-	boost::signals2::scoped_connection death_connection;
+	PBD::ScopedConnection death_connection;
 };
 
 #endif /* __ardour_gtk_region_selection_h__ */
diff --git a/gtk2_ardour/region_view.cc b/gtk2_ardour/region_view.cc
index cdfeceaa8d..770057687a 100644
--- a/gtk2_ardour/region_view.cc
+++ b/gtk2_ardour/region_view.cc
@@ -178,7 +178,7 @@ RegionView::init (Gdk::Color const & basic_color, bool wfd)
 
 	set_height (trackview.current_height());
 
-	_region->StateChanged.connect (*this, boost::bind (&RegionView::region_changed, this, _1));
+	_region->StateChanged.connect (*this, ui_bind (&RegionView::region_changed, this, _1), gui_context());
 	
 	group->signal_event().connect (sigc::bind (sigc::mem_fun (PublicEditor::instance(), &PublicEditor::canvas_region_view_event), group, this));
 
diff --git a/gtk2_ardour/return_ui.cc b/gtk2_ardour/return_ui.cc
index fe1593a4aa..67e05dc47a 100644
--- a/gtk2_ardour/return_ui.cc
+++ b/gtk2_ardour/return_ui.cc
@@ -57,7 +57,7 @@ ReturnUI::ReturnUI (Gtk::Window* parent, boost::shared_ptr<Return> r, Session* s
 	show_all ();
 
 	_return->set_metering (true);
-	_return->input()->changed.connect (input_change_connection, boost::bind (&ReturnUI::ins_changed, this, _1, _2));
+	_return->input()->changed.connect (input_change_connection, ui_bind (&ReturnUI::ins_changed, this, _1, _2), gui_context());
 
 	_gpm.setup_meters ();
 	_gpm.set_fader_name ("ReturnUIFrame");
@@ -110,7 +110,7 @@ ReturnUIWindow::ReturnUIWindow (boost::shared_ptr<Return> r, ARDOUR::Session* s)
 
 	set_name ("ReturnUIWindow");
 
-	r->GoingAway.connect (going_away_connection, boost::bind (&ReturnUIWindow::return_going_away, this));
+	r->GoingAway.connect (going_away_connection, boost::bind (&ReturnUIWindow::return_going_away, this), gui_context());
 	signal_delete_event().connect (sigc::bind (sigc::ptr_fun (just_hide_it), reinterpret_cast<Window *> (this)));
 }
 
diff --git a/gtk2_ardour/return_ui.h b/gtk2_ardour/return_ui.h
index 0f6735c9ea..8c9e87074c 100644
--- a/gtk2_ardour/return_ui.h
+++ b/gtk2_ardour/return_ui.h
@@ -69,7 +69,7 @@ class ReturnUIWindow : public ArdourDialog
 	Gtk::HBox hpacker;
 
 	void return_going_away ();
-	boost::signals2::scoped_connection going_away_connection;
+	PBD::ScopedConnection going_away_connection;
 };
 
 #endif /* __ardour_gtk_return_ui_h__ */
diff --git a/gtk2_ardour/route_params_ui.cc b/gtk2_ardour/route_params_ui.cc
index cf37c2dad4..bfa209d81e 100644
--- a/gtk2_ardour/route_params_ui.cc
+++ b/gtk2_ardour/route_params_ui.cc
@@ -181,8 +181,8 @@ RouteParams_UI::add_routes (RouteList& routes)
 
 		//route_select_list.rows().back().select ();
 
-		route->NameChanged.connect (*this, boost::bind (&RouteParams_UI::route_name_changed, this, boost::weak_ptr<Route>(route)));
-		route->GoingAway.connect (*this, boost::bind (&RouteParams_UI::route_removed, this, boost::weak_ptr<Route>(route)));
+		route->NameChanged.connect (*this, boost::bind (&RouteParams_UI::route_name_changed, this, boost::weak_ptr<Route>(route)), gui_context());
+		route->GoingAway.connect (*this, boost::bind (&RouteParams_UI::route_removed, this, boost::weak_ptr<Route>(route)), gui_context());
 	}
 }
 
@@ -293,8 +293,8 @@ RouteParams_UI::setup_latency_frame ()
 	latency_packer.pack_start (delay_label);
 
 	latency_click_connection = latency_apply_button.signal_clicked().connect (sigc::mem_fun (*latency_widget, &LatencyGUI::finish));
-	_route->signal_latency_changed.connect (latency_connections, sigc::mem_fun (*this, &RouteParams_UI::refresh_latency));
-	_route->initial_delay_changed.connect (latency_connections, sigc::mem_fun (*this, &RouteParams_UI::refresh_latency));
+	_route->signal_latency_changed.connect (latency_connections, boost::bind (&RouteParams_UI::refresh_latency, this), gui_context());
+	_route->initial_delay_changed.connect (latency_connections, boost::bind (&RouteParams_UI::refresh_latency, this), gui_context());
 
 	latency_frame.add (latency_packer);
 	latency_frame.show_all ();
@@ -399,7 +399,7 @@ RouteParams_UI::set_session (Session *sess)
 	if (_session) {
 		boost::shared_ptr<RouteList> r = _session->get_routes();
 		add_routes (*r);
-		_session->RouteAdded.connect (_session_connections, sigc::mem_fun(*this, &RouteParams_UI::add_routes));
+		_session->RouteAdded.connect (_session_connections, ui_bind (&RouteParams_UI::add_routes, this, _1), gui_context());
 		start_updating ();
 	} else {
 		stop_updating ();
@@ -458,7 +458,7 @@ RouteParams_UI::route_selected()
 		setup_processor_boxes();
 		setup_latency_frame ();
 
-		route->processors_changed.connect (_route_processors_connection, boost::bind (&RouteParams_UI::processors_changed, this, _1));
+		route->processors_changed.connect (_route_processors_connection, ui_bind (&RouteParams_UI::processors_changed, this, _1), gui_context());
 		
 		track_input_label.set_text (_route->name());
 
@@ -522,7 +522,7 @@ RouteParams_UI::redirect_selected (boost::shared_ptr<ARDOUR::Processor> proc)
 		SendUI *send_ui = new SendUI (this, send, _session);
 
 		cleanup_view();
-		send->GoingAway.connect (_processor_going_away_connection, boost::bind (&RouteParams_UI::processor_going_away, this, boost::weak_ptr<Processor>(proc)));
+		send->GoingAway.connect (_processor_going_away_connection, boost::bind (&RouteParams_UI::processor_going_away, this, boost::weak_ptr<Processor>(proc)), gui_context());
 		_active_view = send_ui;
 
 		redir_hpane.add2 (*_active_view);
@@ -533,7 +533,7 @@ RouteParams_UI::redirect_selected (boost::shared_ptr<ARDOUR::Processor> proc)
 		ReturnUI *return_ui = new ReturnUI (this, retrn, _session);
 
 		cleanup_view();
-		retrn->GoingAway.connect (_processor_going_away_connection, boost::bind (&RouteParams_UI::processor_going_away, this, boost::weak_ptr<Processor>(proc)));
+		retrn->GoingAway.connect (_processor_going_away_connection, boost::bind (&RouteParams_UI::processor_going_away, this, boost::weak_ptr<Processor>(proc)), gui_context());
 		_active_view = return_ui;
 
 		redir_hpane.add2 (*_active_view);
@@ -544,7 +544,7 @@ RouteParams_UI::redirect_selected (boost::shared_ptr<ARDOUR::Processor> proc)
 		GenericPluginUI *plugin_ui = new GenericPluginUI (plugin_insert, true);
 
 		cleanup_view();
-		plugin_insert->plugin()->GoingAway.connect (_processor_going_away_connection, boost::bind (&RouteParams_UI::plugin_going_away, this, PreFader));
+		plugin_insert->plugin()->GoingAway.connect (_processor_going_away_connection, boost::bind (&RouteParams_UI::plugin_going_away, this, PreFader), gui_context());
 		plugin_ui->start_updating (0);
 		_active_view = plugin_ui;
 
@@ -556,7 +556,7 @@ RouteParams_UI::redirect_selected (boost::shared_ptr<ARDOUR::Processor> proc)
 		PortInsertUI *portinsert_ui = new PortInsertUI (this, _session, port_insert);
 
 		cleanup_view();
-		port_insert->GoingAway.connect (_processor_going_away_connection, boost::bind (&RouteParams_UI::processor_going_away, this, boost::weak_ptr<Processor> (proc)));
+		port_insert->GoingAway.connect (_processor_going_away_connection, boost::bind (&RouteParams_UI::processor_going_away, this, boost::weak_ptr<Processor> (proc)), gui_context());
 		_active_view = portinsert_ui;
 
 		redir_hpane.pack2 (*_active_view);
diff --git a/gtk2_ardour/route_params_ui.h b/gtk2_ardour/route_params_ui.h
index a1a9323134..c09d3c65cd 100644
--- a/gtk2_ardour/route_params_ui.h
+++ b/gtk2_ardour/route_params_ui.h
@@ -126,10 +126,10 @@ class RouteParams_UI : public ArdourDialog, public PBD::ScopedConnectionList
 	RouteRedirectSelection  _rr_selection;
 
 	boost::shared_ptr<ARDOUR::Route> _route;
-	boost::signals2::scoped_connection _route_processors_connection;
+	PBD::ScopedConnection _route_processors_connection;
 
 	boost::shared_ptr<ARDOUR::Processor> _processor;
-	boost::signals2::scoped_connection _processor_going_away_connection;
+	PBD::ScopedConnection _processor_going_away_connection;
 
 
 	enum ConfigView {
diff --git a/gtk2_ardour/route_processor_selection.cc b/gtk2_ardour/route_processor_selection.cc
index 2f4a31a3e0..4e934b0a3c 100644
--- a/gtk2_ardour/route_processor_selection.cc
+++ b/gtk2_ardour/route_processor_selection.cc
@@ -94,7 +94,7 @@ RouteRedirectSelection::add (boost::shared_ptr<Route> r)
 {
 	if (find (routes.begin(), routes.end(), r) == routes.end()) {
 		routes.push_back (r);
-		r->GoingAway.connect (*this, boost::bind (&RouteRedirectSelection::removed, this, boost::weak_ptr<Route>(r)));
+		r->GoingAway.connect (*this, boost::bind (&RouteRedirectSelection::removed, this, boost::weak_ptr<Route>(r)), gui_context());
 		RoutesChanged();
 	}
 }
diff --git a/gtk2_ardour/route_time_axis.cc b/gtk2_ardour/route_time_axis.cc
index 442fb959c4..0e5088cd26 100644
--- a/gtk2_ardour/route_time_axis.cc
+++ b/gtk2_ardour/route_time_axis.cc
@@ -193,9 +193,9 @@ RouteTimeAxisView::RouteTimeAxisView (PublicEditor& ed, Session* sess, boost::sh
 	}
 
 	controls_hbox.pack_start(gm.get_level_meter(), false, false);
-	_route->meter_change.connect (*this, boost::bind (&RouteTimeAxisView::meter_changed, this, _1));
-	_route->input()->changed.connect (*this, boost::bind (&RouteTimeAxisView::io_changed, this, _1, _2));
-	_route->output()->changed.connect (*this, boost::bind (&RouteTimeAxisView::io_changed, this, _1, _2));
+	_route->meter_change.connect (*this, ui_bind (&RouteTimeAxisView::meter_changed, this, _1), gui_context());
+	_route->input()->changed.connect (*this, ui_bind (&RouteTimeAxisView::io_changed, this, _1, _2), gui_context());
+	_route->output()->changed.connect (*this, ui_bind (&RouteTimeAxisView::io_changed, this, _1, _2), gui_context());
 
 	controls_table.attach (*mute_button, 6, 7, 0, 1, Gtk::FILL|Gtk::EXPAND, Gtk::FILL|Gtk::EXPAND, 0, 0);
 	controls_table.attach (*solo_button, 7, 8, 0, 1, Gtk::FILL|Gtk::EXPAND, Gtk::FILL|Gtk::EXPAND, 0, 0);
@@ -234,19 +234,19 @@ RouteTimeAxisView::RouteTimeAxisView (PublicEditor& ed, Session* sess, boost::sh
 
 	_y_position = -1;
 
-	_route->mute_changed.connect (*this, boost::bind (&RouteUI::mute_changed, this, _1));
-	_route->solo_changed.connect (*this, boost::bind (&RouteUI::solo_changed, this, _1));
-	_route->processors_changed.connect (*this, boost::bind (&RouteTimeAxisView::processors_changed, this, _1));
-	_route->NameChanged.connect (*this, boost::bind (&RouteTimeAxisView::route_name_changed, this));
-	_route->solo_isolated_changed.connect (*this, boost::bind (&RouteUI::solo_changed, this, _1));
+	_route->mute_changed.connect (*this, ui_bind (&RouteUI::mute_changed, this, _1), gui_context());
+	_route->solo_changed.connect (*this, ui_bind (&RouteUI::solo_changed, this, _1), gui_context());
+	_route->processors_changed.connect (*this, ui_bind (&RouteTimeAxisView::processors_changed, this, _1), gui_context());
+	_route->NameChanged.connect (*this, boost::bind (&RouteTimeAxisView::route_name_changed, this), gui_context());
+	_route->solo_isolated_changed.connect (*this, ui_bind (&RouteUI::solo_changed, this, _1), gui_context());
 
 
 	if (is_track()) {
 
-		track()->TrackModeChanged.connect (*this, boost::bind (&RouteTimeAxisView::track_mode_changed, this));
-		track()->FreezeChange.connect (*this, boost::bind (&RouteTimeAxisView::map_frozen, this));
-		track()->DiskstreamChanged.connect (*this, boost::bind (&RouteTimeAxisView::diskstream_changed, this));
-		get_diskstream()->SpeedChanged.connect (*this, boost::bind (&RouteTimeAxisView::speed_changed, this));
+		track()->TrackModeChanged.connect (*this, boost::bind (&RouteTimeAxisView::track_mode_changed, this), gui_context());
+		track()->FreezeChange.connect (*this, boost::bind (&RouteTimeAxisView::map_frozen, this), gui_context());
+		track()->DiskstreamChanged.connect (*this, boost::bind (&RouteTimeAxisView::diskstream_changed, this), gui_context());
+		get_diskstream()->SpeedChanged.connect (*this, boost::bind (&RouteTimeAxisView::speed_changed, this), gui_context());
 
 		/* pick up the correct freeze state */
 		map_frozen ();
@@ -532,7 +532,7 @@ RouteTimeAxisView::build_display_menu ()
 
 		if (!Profile->get_sae()) {
 			items.push_back (MenuElem (_("Alignment"), *alignment_menu));
-			get_diskstream()->AlignmentStyleChanged.connect (route_connections, boost::bind (&RouteTimeAxisView::align_style_changed, this));
+			get_diskstream()->AlignmentStyleChanged.connect (route_connections, boost::bind (&RouteTimeAxisView::align_style_changed, this), gui_context());
 
 			RadioMenuItem::Group mode_group;
 			items.push_back (RadioMenuElem (mode_group, _("Normal mode"), sigc::bind (
@@ -564,7 +564,7 @@ RouteTimeAxisView::build_display_menu ()
 			}
 		}
 
-		get_diskstream()->AlignmentStyleChanged.connect (route_connections, boost::bind (&RouteTimeAxisView::align_style_changed, this));
+		get_diskstream()->AlignmentStyleChanged.connect (route_connections, boost::bind (&RouteTimeAxisView::align_style_changed, this), gui_context());
 
 		mode_menu = build_mode_menu();
 		if (mode_menu)
diff --git a/gtk2_ardour/route_ui.cc b/gtk2_ardour/route_ui.cc
index 3eb72a9b53..d84cc8ba36 100644
--- a/gtk2_ardour/route_ui.cc
+++ b/gtk2_ardour/route_ui.cc
@@ -136,11 +136,11 @@ RouteUI::init ()
 	show_sends_button->set_self_managed (true);
 	UI::instance()->set_tip (show_sends_button, _("make mixer strips show sends to this bus"), "");
 
-	_session->SoloChanged.connect (_session_connections, sigc::mem_fun(*this, &RouteUI::solo_changed_so_update_mute));
-	_session->TransportStateChange.connect (_session_connections, sigc::mem_fun (*this, &RouteUI::check_rec_enable_sensitivity));
-	_session->RecordStateChanged.connect (_session_connections, boost::bind (&RouteUI::session_rec_enable_changed, this));
+	_session->SoloChanged.connect (_session_connections, boost::bind (&RouteUI::solo_changed_so_update_mute, this), gui_context());
+	_session->TransportStateChange.connect (_session_connections, boost::bind (&RouteUI::check_rec_enable_sensitivity, this), gui_context());
+	_session->RecordStateChanged.connect (_session_connections, boost::bind (&RouteUI::session_rec_enable_changed, this), gui_context());
 
-	Config->ParameterChanged.connect (*this, boost::bind (&RouteUI::parameter_changed, this, _1));
+	Config->ParameterChanged.connect (*this, ui_bind (&RouteUI::parameter_changed, this, _1), gui_context());
 }
 
 void
@@ -188,22 +188,22 @@ RouteUI::set_route (boost::shared_ptr<Route> rp)
 	}
 
 	if (self_destruct) {
-		rp->GoingAway.connect (route_connections, boost::bind (&RouteUI::self_delete, this));
+		rp->GoingAway.connect (route_connections, boost::bind (&RouteUI::self_delete, this), gui_context());
 	}
 
 	mute_button->set_controllable (_route->mute_control());
 	solo_button->set_controllable (_route->solo_control());
 
-	_route->active_changed.connect (route_connections, boost::bind (&RouteUI::route_active_changed, this));
-	_route->mute_changed.connect (route_connections, boost::bind (&RouteUI::mute_changed, this, _1));
-	_route->solo_changed.connect (route_connections, boost::bind (&RouteUI::solo_changed, this, _1));
-	_route->listen_changed.connect (route_connections, boost::bind (&RouteUI::listen_changed, this, _1));
-	_route->solo_isolated_changed.connect (route_connections, boost::bind (&RouteUI::solo_changed, this, _1));
+	_route->active_changed.connect (route_connections, boost::bind (&RouteUI::route_active_changed, this), gui_context());
+	_route->mute_changed.connect (route_connections, ui_bind (&RouteUI::mute_changed, this, _1), gui_context());
+	_route->solo_changed.connect (route_connections, ui_bind (&RouteUI::solo_changed, this, _1), gui_context());
+	_route->listen_changed.connect (route_connections, ui_bind (&RouteUI::listen_changed, this, _1), gui_context());
+	_route->solo_isolated_changed.connect (route_connections, ui_bind (&RouteUI::solo_changed, this, _1), gui_context());
 
 	if (_session->writable() && is_track()) {
 		boost::shared_ptr<Track> t = boost::dynamic_pointer_cast<Track>(_route);
 
-		t->diskstream()->RecordEnableChanged.connect (route_connections, boost::bind (&RouteUI::route_rec_enable_changed, this));
+		t->diskstream()->RecordEnableChanged.connect (route_connections, boost::bind (&RouteUI::route_rec_enable_changed, this), gui_context());
 
 		rec_enable_button->show();
  		rec_enable_button->set_controllable (t->rec_enable_control());
@@ -893,14 +893,14 @@ RouteUI::build_solo_menu (void)
 	check = new CheckMenuItem(_("Solo Isolate"));
 	check->set_active (_route->solo_isolated());
 	check->signal_toggled().connect (sigc::bind (sigc::mem_fun (*this, &RouteUI::toggle_solo_isolated), check));
-	_route->solo_isolated_changed.connect (route_connections, boost::bind (&RouteUI::solo_isolated_toggle, this, _1, check));
+	_route->solo_isolated_changed.connect (route_connections, ui_bind (&RouteUI::solo_isolated_toggle, this, _1, check), gui_context());
 	items.push_back (CheckMenuElem(*check));
 	check->show_all();
 
 	check = new CheckMenuItem(_("Solo Safe"));
 	check->set_active (_route->solo_safe());
 	check->signal_toggled().connect (sigc::bind (sigc::mem_fun (*this, &RouteUI::toggle_solo_safe), check));
-	_route->solo_safe_changed.connect (route_connections, boost::bind (&RouteUI::solo_safe_toggle, this, _1, check));
+	_route->solo_safe_changed.connect (route_connections, ui_bind (&RouteUI::solo_safe_toggle, this, _1, check), gui_context());
 	items.push_back (CheckMenuElem(*check));
 	check->show_all();
 
@@ -946,7 +946,7 @@ RouteUI::build_mute_menu(void)
 	//items.push_back (SeparatorElem());
 	// items.push_back (MenuElem (_("MIDI Bind"), sigc::mem_fun (*mute_button, &BindableToggleButton::midi_learn)));
 
-	_route->mute_points_changed.connect (route_connections, boost::bind (&RouteUI::muting_change, this));
+	_route->mute_points_changed.connect (route_connections, boost::bind (&RouteUI::muting_change, this), gui_context());
 }
 
 void
diff --git a/gtk2_ardour/selection.cc b/gtk2_ardour/selection.cc
index 05cd154831..edba77140d 100644
--- a/gtk2_ardour/selection.cc
+++ b/gtk2_ardour/selection.cc
@@ -25,6 +25,7 @@
 #include "ardour/playlist.h"
 #include "ardour/rc_configuration.h"
 
+#include "gui_thread.h"
 #include "midi_cut_buffer.h"
 #include "region_view.h"
 #include "selection.h"
@@ -209,7 +210,7 @@ Selection::toggle (TimeAxisView* track)
 
 	if ((i = find (tracks.begin(), tracks.end(), track)) == tracks.end()) {
 		void (Selection::*pmf)(TimeAxisView*) = &Selection::remove;
-		track->GoingAway.connect (*this, boost::bind (pmf, this, track));
+		track->GoingAway.connect (*this, boost::bind (pmf, this, track), gui_context());
 		tracks.push_back (track);
 	} else {
 		tracks.erase (i);
@@ -338,7 +339,7 @@ Selection::add (const TrackViewList& track_list)
 
 	for (list<TimeAxisView*>::const_iterator i = added.begin(); i != added.end(); ++i) {
 		void (Selection::*pmf)(TimeAxisView*) = &Selection::remove;
-		(*i)->GoingAway.connect (*this, boost::bind (pmf, this, (*i)));
+		(*i)->GoingAway.connect (*this, boost::bind (pmf, this, (*i)), gui_context());
 	}
 
 	if (!added.empty()) {
@@ -949,7 +950,7 @@ Selection::add (Marker* m)
 
 		void (Selection::*pmf)(Marker*) = &Selection::remove;
 
-		m->GoingAway.connect (*this, boost::bind (pmf, this, m));
+		m->GoingAway.connect (*this, boost::bind (pmf, this, m), gui_context());
 
 		markers.push_back (m);
 		MarkersChanged();
diff --git a/gtk2_ardour/send_ui.cc b/gtk2_ardour/send_ui.cc
index 4c1bb9fec3..0b24587651 100644
--- a/gtk2_ardour/send_ui.cc
+++ b/gtk2_ardour/send_ui.cc
@@ -61,8 +61,8 @@ SendUI::SendUI (Gtk::Window* parent, boost::shared_ptr<Send> s, Session* session
 
 	_send->set_metering (true);
 
-	_send->input()->changed.connect (connections, boost::bind (&SendUI::ins_changed, this, _1, _2));
-	_send->output()->changed.connect (connections, boost::bind (&SendUI::outs_changed, this, _1, _2));
+	_send->input()->changed.connect (connections, ui_bind (&SendUI::ins_changed, this, _1, _2), gui_context());
+	_send->output()->changed.connect (connections, ui_bind (&SendUI::outs_changed, this, _1, _2), gui_context());
 
 	_panners.set_width (Wide);
 	_panners.setup_pan ();
@@ -130,7 +130,7 @@ SendUIWindow::SendUIWindow (boost::shared_ptr<Send> s, Session* session)
 
 	set_name ("SendUIWindow");
 
-	s->GoingAway.connect (going_away_connection, boost::bind (&SendUIWindow::send_going_away, this));
+	s->GoingAway.connect (going_away_connection, boost::bind (&SendUIWindow::send_going_away, this), gui_context());
 
 	signal_delete_event().connect (sigc::bind (
 					       sigc::ptr_fun (just_hide_it),
diff --git a/gtk2_ardour/send_ui.h b/gtk2_ardour/send_ui.h
index 2c71466518..171b913702 100644
--- a/gtk2_ardour/send_ui.h
+++ b/gtk2_ardour/send_ui.h
@@ -71,7 +71,7 @@ class SendUIWindow : public ArdourDialog
 	Gtk::HBox hpacker;
 
 	void send_going_away ();
-	boost::signals2::scoped_connection going_away_connection;
+	PBD::ScopedConnection going_away_connection;
 };
 
 #endif /* __ardour_gtk_send_ui_h__ */
diff --git a/gtk2_ardour/session_import_dialog.cc b/gtk2_ardour/session_import_dialog.cc
index 5b6b8a71b4..675a3b0603 100644
--- a/gtk2_ardour/session_import_dialog.cc
+++ b/gtk2_ardour/session_import_dialog.cc
@@ -30,6 +30,7 @@
 
 #include <gtkmm2ext/utils.h>
 
+#include "gui_thread.h"
 #include "prompter.h"
 #include "i18n.h"
 
@@ -91,10 +92,10 @@ SessionImportDialog::SessionImportDialog (ARDOUR::Session* target) :
 	ok_button = add_button (_("Import"), Gtk::RESPONSE_ACCEPT);
 	ok_button->signal_clicked().connect (sigc::mem_fun (*this, &SessionImportDialog::do_merge));
 
-	// prompt signals
-	ElementImporter::Rename.connect (connections, boost::bind (&SessionImportDialog::open_rename_dialog, this, _1, _2));
-	ElementImporter::Prompt.connect (connections, boost::bind (&SessionImportDialog::open_prompt_dialog, this, _1));
-
+	// prompt signals XXX: problem - handlers to be in the same thread since they return values
+	ElementImporter::Rename.connect_same_thread (connections, boost::bind (&SessionImportDialog::open_rename_dialog, this, _1, _2));
+	ElementImporter::Prompt.connect_same_thread (connections, boost::bind (&SessionImportDialog::open_prompt_dialog, this, _1));
+		
 	// Finalize
 	show_all();
 }
diff --git a/gtk2_ardour/session_option_editor.cc b/gtk2_ardour/session_option_editor.cc
index 2cc6e253ba..2fb6328c1c 100644
--- a/gtk2_ardour/session_option_editor.cc
+++ b/gtk2_ardour/session_option_editor.cc
@@ -3,6 +3,8 @@
 #include "ardour/auditioner.h"
 #include "ardour/audioengine.h"
 #include "ardour/port.h"
+
+#include "gui_thread.h"
 #include "session_option_editor.h"
 #include "port_matrix.h"
 #include "i18n.h"
@@ -160,9 +162,9 @@ SessionOptionEditor::SessionOptionEditor (Session* s)
 		sigc::mem_fun (*_session_config, &SessionConfiguration::set_sync_source)
 		);
 	
-	s->MTC_PortChanged.connect (_session_connections, boost::bind (&SessionOptionEditor::populate_sync_options, this, s, ssrc));
-	s->MIDIClock_PortChanged.connect (_session_connections, boost::bind (&SessionOptionEditor::populate_sync_options, this, s, ssrc));
-	s->config.ParameterChanged.connect (_session_connections, boost::bind (&SessionOptionEditor::follow_sync_state, this, _1, s, ssrc));
+	s->MTC_PortChanged.connect (_session_connections, boost::bind (&SessionOptionEditor::populate_sync_options, this, s, ssrc), gui_context());
+	s->MIDIClock_PortChanged.connect (_session_connections, boost::bind (&SessionOptionEditor::populate_sync_options, this, s, ssrc), gui_context());
+	s->config.ParameterChanged.connect (_session_connections, ui_bind (&SessionOptionEditor::follow_sync_state, this, _1, s, ssrc), gui_context());
 
 	populate_sync_options (s, ssrc);
 	follow_sync_state (string ("external-sync"), s, ssrc);
diff --git a/gtk2_ardour/splash.cc b/gtk2_ardour/splash.cc
index 6489efcdf7..910e996702 100644
--- a/gtk2_ardour/splash.cc
+++ b/gtk2_ardour/splash.cc
@@ -56,7 +56,7 @@ Splash::Splash ()
 	set_default_size (pixbuf->get_width(), pixbuf->get_height());
 	the_splash = this;
 
-	ARDOUR::BootMessage.connect (msg_connection, boost::bind (&Splash::boot_message, this, _1));
+	ARDOUR::BootMessage.connect (msg_connection, ui_bind (&Splash::boot_message, this, _1), gui_context());
 }
 
 void
diff --git a/gtk2_ardour/streamview.cc b/gtk2_ardour/streamview.cc
index 39f98582c7..a29ad7b4cc 100644
--- a/gtk2_ardour/streamview.cc
+++ b/gtk2_ardour/streamview.cc
@@ -79,12 +79,12 @@ StreamView::StreamView (RouteTimeAxisView& tv, ArdourCanvas::Group* group)
 			canvas_rect, &_trackview));
 
 	if (_trackview.is_track()) {
-		_trackview.track()->DiskstreamChanged.connect (*this, boost::bind (&StreamView::diskstream_changed, this));
-		_trackview.get_diskstream()->RecordEnableChanged.connect (*this, boost::bind (&StreamView::rec_enable_changed, this));
+		_trackview.track()->DiskstreamChanged.connect (*this, boost::bind (&StreamView::diskstream_changed, this), gui_context());
+		_trackview.get_diskstream()->RecordEnableChanged.connect (*this, boost::bind (&StreamView::rec_enable_changed, this), gui_context());
 
-		_trackview.session()->TransportStateChange.connect (*this, boost::bind (&StreamView::transport_changed, this));
-		_trackview.session()->TransportLooped.connect (*this, boost::bind (&StreamView::transport_looped, this));
-		_trackview.session()->RecordStateChanged.connect (*this, boost::bind (&StreamView::sess_rec_enable_changed, this));
+		_trackview.session()->TransportStateChange.connect (*this, boost::bind (&StreamView::transport_changed, this), gui_context());
+		_trackview.session()->TransportLooped.connect (*this, boost::bind (&StreamView::transport_looped, this), gui_context());
+		_trackview.session()->RecordStateChanged.connect (*this, boost::bind (&StreamView::sess_rec_enable_changed, this), gui_context());
 	}
 
 	ColorsChanged.connect (sigc::mem_fun (*this, &StreamView::color_handler));
@@ -231,7 +231,7 @@ StreamView::display_diskstream (boost::shared_ptr<Diskstream> ds)
 {
 	playlist_change_connection.disconnect();
 	playlist_changed (ds);
-	ds->PlaylistChanged.connect (playlist_change_connection, boost::bind (&StreamView::playlist_changed_weak, this, boost::weak_ptr<Diskstream> (ds)));
+	ds->PlaylistChanged.connect (playlist_change_connection, boost::bind (&StreamView::playlist_changed_weak, this, boost::weak_ptr<Diskstream> (ds)), gui_context());
 }
 
 void
@@ -353,9 +353,9 @@ StreamView::playlist_changed (boost::shared_ptr<Diskstream> ds)
 
 	/* catch changes */
 
-	ds->playlist()->Modified.connect (playlist_connections, boost::bind (&StreamView::playlist_modified_weak, this, ds));
-	ds->playlist()->RegionAdded.connect (playlist_connections, boost::bind (&StreamView::add_region_view_weak, this, _1));
-	ds->playlist()->RegionRemoved.connect (playlist_connections, boost::bind (&StreamView::remove_region_view, this, _1));
+	ds->playlist()->Modified.connect (playlist_connections, boost::bind (&StreamView::playlist_modified_weak, this, ds), gui_context());
+	ds->playlist()->RegionAdded.connect (playlist_connections, ui_bind (&StreamView::add_region_view_weak, this, _1), gui_context());
+	ds->playlist()->RegionRemoved.connect (playlist_connections, ui_bind (&StreamView::remove_region_view, this, _1), gui_context());
 }
 
 void
diff --git a/gtk2_ardour/streamview.h b/gtk2_ardour/streamview.h
index effb9431d0..d28dc37133 100644
--- a/gtk2_ardour/streamview.h
+++ b/gtk2_ardour/streamview.h
@@ -161,7 +161,7 @@ protected:
 	uint32_t   stream_base_color; ///< Background color
 
 	PBD::ScopedConnectionList playlist_connections;
-	boost::signals2::scoped_connection playlist_change_connection;
+	PBD::ScopedConnection playlist_change_connection;
 
 	ARDOUR::layer_t _layers;
 	LayerDisplay    _layer_display;
diff --git a/gtk2_ardour/strip_silence_dialog.cc b/gtk2_ardour/strip_silence_dialog.cc
index ab1297d6bc..3592668cf8 100644
--- a/gtk2_ardour/strip_silence_dialog.cc
+++ b/gtk2_ardour/strip_silence_dialog.cc
@@ -22,8 +22,10 @@
 #include <gtkmm/stock.h>
 #include "ardour/audioregion.h"
 #include "ardour/audiosource.h"
+
 #include "ardour/dB.h"
 #include "ardour_ui.h"
+#include "gui_thread.h"
 #include "strip_silence_dialog.h"
 #include "canvas_impl.h"
 #include "waveview.h"
@@ -129,7 +131,7 @@ StripSilenceDialog::create_waves ()
 	int n = 0;
 
 	for (std::list<Wave>::iterator i = _waves.begin(); i != _waves.end(); ++i) {
-		if (i->region->audio_source(0)->peaks_ready (boost::bind (&StripSilenceDialog::peaks_ready, this), _peaks_ready_connection)) {
+		if (i->region->audio_source(0)->peaks_ready (boost::bind (&StripSilenceDialog::peaks_ready, this), _peaks_ready_connection, gui_context())) {
 			i->view = new WaveView (*(_canvas->root()));
 			i->view->property_data_src() = static_cast<gpointer>(i->region.get());
 			i->view->property_cache() = WaveView::create_cache ();
diff --git a/gtk2_ardour/strip_silence_dialog.h b/gtk2_ardour/strip_silence_dialog.h
index f79abb8eb9..927764e57c 100644
--- a/gtk2_ardour/strip_silence_dialog.h
+++ b/gtk2_ardour/strip_silence_dialog.h
@@ -66,5 +66,5 @@ private:
 	int _wave_width;
 	int _wave_height;
 
-	boost::signals2::scoped_connection _peaks_ready_connection;
+	PBD::ScopedConnection _peaks_ready_connection;
 };
diff --git a/gtk2_ardour/tape_region_view.cc b/gtk2_ardour/tape_region_view.cc
index 6fd2570c27..31baf17234 100644
--- a/gtk2_ardour/tape_region_view.cc
+++ b/gtk2_ardour/tape_region_view.cc
@@ -71,7 +71,7 @@ TapeAudioRegionView::init (Gdk::Color const & basic_color, bool /*wfw*/)
 	/* every time the wave data changes and peaks are ready, redraw */
 
 	for (uint32_t n = 0; n < audio_region()->n_channels(); ++n) {
-		audio_region()->audio_source(n)->PeaksReady.connect (*this, boost::bind (&TapeAudioRegionView::update, this, n));
+		audio_region()->audio_source(n)->PeaksReady.connect (*this, boost::bind (&TapeAudioRegionView::update, this, n), gui_context());
 	}
 
 }
diff --git a/gtk2_ardour/time_axis_view.cc b/gtk2_ardour/time_axis_view.cc
index d3e3e88003..cac49687a3 100644
--- a/gtk2_ardour/time_axis_view.cc
+++ b/gtk2_ardour/time_axis_view.cc
@@ -40,6 +40,7 @@
 #include "ardour/location.h"
 
 #include "ardour_ui.h"
+#include "gui_thread.h"
 #include "public_editor.h"
 #include "time_axis_view.h"
 #include "region_view.h"
@@ -924,7 +925,7 @@ TimeAxisView::add_ghost (RegionView* rv)
 
 	if(gr) {
 		ghosts.push_back(gr);
-		gr->GoingAway.connect (*this, boost::bind (&TimeAxisView::erase_ghost, this, _1));
+		gr->GoingAway.connect (*this, ui_bind (&TimeAxisView::erase_ghost, this, _1), gui_context());
 	}
 }