Merge branch 'master' into windows

38 files changed, 246 insertions, 96 deletions

diff --git a/gtk2_ardour/midi_tracer.cc b/gtk2_ardour/midi_tracer.cc
index e447c59f3b..e0deb6dce8 100644
--- a/gtk2_ardour/midi_tracer.cc
+++ b/gtk2_ardour/midi_tracer.cc
@@ -303,7 +303,12 @@ MidiTracer::tracer (Parser&, byte* msg, size_t len)
 			s += snprintf (
 				&buf[s], bufsize, " MTC full frame to %02d:%02d:%02d:%02d\n", msg[5] & 0x1f, msg[6], msg[7], msg[8]
 				);
+		} else if (len == 3 && msg[0] == MIDI::position) {
 
+			/* MIDI Song Position */
+			uint16_t midi_beats = (uint16_t) msg[1];
+			midi_beats |= msg[2];
+			s += snprintf (&buf[s], bufsize, "%16s %d\n", "Position", (int) midi_beats);
 		} else {
 
 			/* other sys-ex */
diff --git a/gtk2_ardour/port_matrix.cc b/gtk2_ardour/port_matrix.cc
index d406b8ed01..5c21d7ff25 100644
--- a/gtk2_ardour/port_matrix.cc
+++ b/gtk2_ardour/port_matrix.cc
@@ -152,6 +152,7 @@ PortMatrix::init ()
 
 	/* and also bundles */
 	_session->BundleAdded.connect (_session_connections, invalidator (*this), boost::bind (&PortMatrix::setup_global_ports, this), gui_context());
+	_session->BundleRemoved.connect (_session_connections, invalidator (*this), boost::bind (&PortMatrix::setup_global_ports, this), gui_context());
 
 	/* and also ports */
 	_session->engine().PortRegisteredOrUnregistered.connect (_session_connections, invalidator (*this), boost::bind (&PortMatrix::setup_global_ports, this), gui_context());
@@ -180,6 +181,7 @@ 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, invalidator (*this), boost::bind (&PortMatrix::route_processors_changed, this, _1), gui_context());
+		(*i)->DropReferences.connect (_route_connections, invalidator (*this), boost::bind (&PortMatrix::routes_changed, this), gui_context());
 	}
 }
 
@@ -198,6 +200,7 @@ PortMatrix::route_processors_changed (RouteProcessorChange c)
 void
 PortMatrix::routes_changed ()
 {
+	if (!_session) return;
 	reconnect_to_routes ();
 	setup_global_ports ();
 }
@@ -206,7 +209,10 @@ PortMatrix::routes_changed ()
 void
 PortMatrix::setup ()
 {
-	if (!_session) return; // session went away
+	if (!_session) {
+		_route_connections.drop_connections ();
+		return; // session went away
+	}
 
 	/* this needs to be done first, as the visible_ports() method uses the
 	   notebook state to decide which ports are being shown */
diff --git a/libs/ardour/amp.cc b/libs/ardour/amp.cc
index f60240fd57..c97d624440 100644
--- a/libs/ardour/amp.cc
+++ b/libs/ardour/amp.cc
@@ -61,7 +61,7 @@ Amp::display_name() const
 }
 
 bool
-Amp::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+Amp::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	out = in;
 	return true;
diff --git a/libs/ardour/ardour/amp.h b/libs/ardour/ardour/amp.h
index 23cc0ad0a8..e21cf62d62 100644
--- a/libs/ardour/ardour/amp.h
+++ b/libs/ardour/ardour/amp.h
@@ -40,7 +40,7 @@ public:
 
 	bool visible () const;
 
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	bool configure_io (ChanCount in, ChanCount out);
 
 	void run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pframes_t nframes, bool);
diff --git a/libs/ardour/ardour/audio_unit.h b/libs/ardour/ardour/audio_unit.h
index 36e82da802..007390b34a 100644
--- a/libs/ardour/ardour/audio_unit.h
+++ b/libs/ardour/ardour/audio_unit.h
@@ -104,7 +104,7 @@ class AUPlugin : public ARDOUR::Plugin
 
 	bool has_editor () const;
 
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	ChanCount output_streams() const;
 	ChanCount input_streams() const;
 	bool configure_io (ChanCount in, ChanCount out);
diff --git a/libs/ardour/ardour/capturing_processor.h b/libs/ardour/ardour/capturing_processor.h
index b672d1ac07..5b9ea51557 100644
--- a/libs/ardour/ardour/capturing_processor.h
+++ b/libs/ardour/ardour/capturing_processor.h
@@ -38,7 +38,7 @@ class CapturingProcessor : public Processor
 	int set_block_size (pframes_t nframes);
 	void run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pframes_t nframes, bool result_required);
 	bool configure_io (ChanCount in, ChanCount out);
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	virtual XMLNode& state (bool);
 
   private:
diff --git a/libs/ardour/ardour/delivery.h b/libs/ardour/ardour/delivery.h
index 314b223538..4a6d4368a6 100644
--- a/libs/ardour/ardour/delivery.h
+++ b/libs/ardour/ardour/delivery.h
@@ -67,7 +67,7 @@ public:
 	std::string display_name() const;
 
 	Role role() const { return _role; }
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	bool configure_io (ChanCount in, ChanCount out);
 
 	void run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pframes_t nframes, bool);
diff --git a/libs/ardour/ardour/internal_return.h b/libs/ardour/ardour/internal_return.h
index c7fe04cc42..4d2b32f031 100644
--- a/libs/ardour/ardour/internal_return.h
+++ b/libs/ardour/ardour/internal_return.h
@@ -39,7 +39,7 @@ class InternalReturn : public Return
 
 	void run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pframes_t nframes, bool);
 	bool configure_io (ChanCount, ChanCount);
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 
 	void add_send (InternalSend *);
 	void remove_send (InternalSend *);
diff --git a/libs/ardour/ardour/internal_send.h b/libs/ardour/ardour/internal_send.h
index 8bfb0de887..a7f0f73e6e 100644
--- a/libs/ardour/ardour/internal_send.h
+++ b/libs/ardour/ardour/internal_send.h
@@ -42,7 +42,7 @@ class InternalSend : public Send
 	void cycle_start (pframes_t);
 	void run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pframes_t nframes, bool);
 	bool feeds (boost::shared_ptr<Route> other) const;
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	bool configure_io (ChanCount in, ChanCount out);
 	int  set_block_size (pframes_t);
 
diff --git a/libs/ardour/ardour/meter.h b/libs/ardour/ardour/meter.h
index a4ad8ecff4..df1e381bb4 100644
--- a/libs/ardour/ardour/meter.h
+++ b/libs/ardour/ardour/meter.h
@@ -56,7 +56,7 @@ public:
 	void reset ();
 	void reset_max ();
 
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	bool configure_io (ChanCount in, ChanCount out);
 
 	/* special method for meter, to ensure that it can always handle the maximum
diff --git a/libs/ardour/ardour/monitor_processor.h b/libs/ardour/ardour/monitor_processor.h
index 5b724b5e8d..64d3b86bfb 100644
--- a/libs/ardour/ardour/monitor_processor.h
+++ b/libs/ardour/ardour/monitor_processor.h
@@ -118,7 +118,7 @@ public:
 	int set_state (const XMLNode&, int /* version */);
 
 	bool configure_io (ChanCount in, ChanCount out);
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 
 	void set_cut_all (bool);
 	void set_dim_all (bool);
diff --git a/libs/ardour/ardour/panner_shell.h b/libs/ardour/ardour/panner_shell.h
index 7d24adb46f..dba5826370 100644
--- a/libs/ardour/ardour/panner_shell.h
+++ b/libs/ardour/ardour/panner_shell.h
@@ -53,7 +53,7 @@ public:
 
 	std::string describe_parameter (Evoral::Parameter param);
 
-	bool can_support_io_configuration (const ChanCount& /*in*/, ChanCount& /*out*/) const { return true; };
+	bool can_support_io_configuration (const ChanCount& /*in*/, ChanCount& /*out*/) { return true; };
 	void configure_io (ChanCount in, ChanCount out);
 
 	/// The fundamental Panner function
diff --git a/libs/ardour/ardour/plugin.h b/libs/ardour/ardour/plugin.h
index 9e4f5c40fd..55b76fbb08 100644
--- a/libs/ardour/ardour/plugin.h
+++ b/libs/ardour/ardour/plugin.h
@@ -242,7 +242,7 @@ class Plugin : public PBD::StatefulDestructible, public Latent
 	/* specific types of plugins can overload this. As of September 2008, only
 	   AUPlugin does this.
 	*/
-	virtual bool can_support_io_configuration (const ChanCount& /*in*/, ChanCount& /*out*/) const { return false; }
+	virtual bool can_support_io_configuration (const ChanCount& /*in*/, ChanCount& /*out*/) { return false; }
 	virtual ChanCount output_streams() const;
 	virtual ChanCount input_streams() const;
 
diff --git a/libs/ardour/ardour/plugin_insert.h b/libs/ardour/ardour/plugin_insert.h
index d80c759cff..a1b9c5a685 100644
--- a/libs/ardour/ardour/plugin_insert.h
+++ b/libs/ardour/ardour/plugin_insert.h
@@ -69,7 +69,7 @@ class PluginInsert : public Processor
 	bool     set_count (uint32_t num);
 	uint32_t get_count () const { return _plugins.size(); }
 
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	bool configure_io (ChanCount in, ChanCount out);
 
 	bool has_no_inputs() const;
@@ -160,6 +160,8 @@ class PluginInsert : public Processor
 	BufferSet _signal_analysis_inputs;
 	BufferSet _signal_analysis_outputs;
 
+	ChanCount midi_bypass;
+
 	/** Description of how we can match our plugin's IO to our own insert IO */
 	struct Match {
 		Match () : method (Impossible), plugins (0) {}
@@ -170,7 +172,7 @@ class PluginInsert : public Processor
 		ChanCount hide;        ///< number of channels to hide
 	};
 
-	Match private_can_support_io_configuration (ChanCount const &, ChanCount &) const;
+	Match private_can_support_io_configuration (ChanCount const &, ChanCount &);
 
 	/** details of the match currently being used */
 	Match _match;
diff --git a/libs/ardour/ardour/port_insert.h b/libs/ardour/ardour/port_insert.h
index 657c2c0de6..abd9fb73cc 100644
--- a/libs/ardour/ardour/port_insert.h
+++ b/libs/ardour/ardour/port_insert.h
@@ -57,7 +57,7 @@ class PortInsert : public IOProcessor
 
 	bool set_name (const std::string& name);
 
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	bool configure_io (ChanCount in, ChanCount out);
 
 	void activate ();
diff --git a/libs/ardour/ardour/processor.h b/libs/ardour/ardour/processor.h
index d497f56dd3..772ae3520d 100644
--- a/libs/ardour/ardour/processor.h
+++ b/libs/ardour/ardour/processor.h
@@ -82,7 +82,7 @@ class Processor : public SessionObject, public Automatable, public Latent
 
 	/* Derived classes should override these, or processor appears as an in-place pass-through */
 
-	virtual bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const = 0;
+	virtual bool can_support_io_configuration (const ChanCount& in, ChanCount& out) = 0;
 	virtual ChanCount input_streams () const { return _configured_input; }
 	virtual ChanCount output_streams() const { return _configured_output; }
 
diff --git a/libs/ardour/ardour/return.h b/libs/ardour/ardour/return.h
index 55ca2d84f6..6dcd6ac2fc 100644
--- a/libs/ardour/ardour/return.h
+++ b/libs/ardour/ardour/return.h
@@ -56,7 +56,7 @@ public:
 
 	uint32_t pans_required() const { return _configured_input.n_audio(); }
 
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	bool configure_io (ChanCount in, ChanCount out);
 
 	static uint32_t how_many_returns();
diff --git a/libs/ardour/ardour/send.h b/libs/ardour/ardour/send.h
index fa023a3b68..1a21d1d050 100644
--- a/libs/ardour/ardour/send.h
+++ b/libs/ardour/ardour/send.h
@@ -56,7 +56,7 @@ class Send : public Delivery
 
 	void run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pframes_t nframes, bool);
 
-	bool can_support_io_configuration (const ChanCount& in, ChanCount& out) const;
+	bool can_support_io_configuration (const ChanCount& in, ChanCount& out);
 	bool configure_io (ChanCount in, ChanCount out);
 
 	void activate ();
diff --git a/libs/ardour/ardour/ticker.h b/libs/ardour/ardour/ticker.h
index da728a5d54..b6e5376c12 100644
--- a/libs/ardour/ardour/ticker.h
+++ b/libs/ardour/ardour/ticker.h
@@ -19,6 +19,7 @@
 */
 
 #include <boost/noncopyable.hpp>
+#include <boost/scoped_ptr.hpp>
 
 #include "pbd/signals.h"
 
@@ -42,7 +43,7 @@ class MidiClockTicker : public SessionHandlePtr, boost::noncopyable
 {
 public:
 	MidiClockTicker ();
-	virtual ~MidiClockTicker() {}
+	virtual ~MidiClockTicker();
 
 	void tick (const framepos_t& transport_frames);
 
@@ -63,6 +64,9 @@ public:
 	/// slot for the signal session::TransportLooped
 	void transport_looped();
 
+	/// slot for the signal session::Located
+	void session_located();
+
 	/// pulses per quarter note (default 24)
 	void set_ppqn(int ppqn) { _ppqn = ppqn; }
 
@@ -71,13 +75,16 @@ private:
 	int          _ppqn;
 	double       _last_tick;
 
+	class Position;
+	boost::scoped_ptr<Position> _pos;
+
 	double one_ppqn_in_frames (framepos_t transport_position);
 
 	void send_midi_clock_event (pframes_t offset);
 	void send_start_event (pframes_t offset);
 	void send_continue_event (pframes_t offset);
 	void send_stop_event (pframes_t offset);
-	void send_position_event (framepos_t transport_position, pframes_t offset);
+	void send_position_event (uint32_t midi_clocks, pframes_t offset);
 };
 
 }
diff --git a/libs/ardour/ardour/unknown_processor.h b/libs/ardour/ardour/unknown_processor.h
index 36981030ce..61a5734df2 100644
--- a/libs/ardour/ardour/unknown_processor.h
+++ b/libs/ardour/ardour/unknown_processor.h
@@ -49,7 +49,7 @@ public:
 		return false;
 	}
 
-	bool can_support_io_configuration (const ChanCount &, ChanCount &) const {
+	bool can_support_io_configuration (const ChanCount &, ChanCount &) {
 		return false;
 	}
 
diff --git a/libs/ardour/audio_unit.cc b/libs/ardour/audio_unit.cc
index 3636ebf941..83d2c46ba6 100644
--- a/libs/ardour/audio_unit.cc
+++ b/libs/ardour/audio_unit.cc
@@ -998,7 +998,7 @@ AUPlugin::output_streams() const
 }
 
 bool
-AUPlugin::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+AUPlugin::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	// Note: We never attempt to multiply-instantiate plugins to meet io configurations.
 
diff --git a/libs/ardour/capturing_processor.cc b/libs/ardour/capturing_processor.cc
index c4b463aba7..4a31d92cc8 100644
--- a/libs/ardour/capturing_processor.cc
+++ b/libs/ardour/capturing_processor.cc
@@ -62,7 +62,7 @@ CapturingProcessor::configure_io (ChanCount in, ChanCount out)
 }
 
 bool
-CapturingProcessor::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+CapturingProcessor::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	out = in;
 	return true;
diff --git a/libs/ardour/delivery.cc b/libs/ardour/delivery.cc
index 9eaf843f7c..dfbe4c960a 100644
--- a/libs/ardour/delivery.cc
+++ b/libs/ardour/delivery.cc
@@ -124,7 +124,7 @@ Delivery::display_name () const
 }
 
 bool
-Delivery::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+Delivery::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	if (_role == Main) {
 
diff --git a/libs/ardour/internal_return.cc b/libs/ardour/internal_return.cc
index af6b6110b6..fc5963603b 100644
--- a/libs/ardour/internal_return.cc
+++ b/libs/ardour/internal_return.cc
@@ -80,7 +80,7 @@ InternalReturn::get_state()
 }
 
 bool
-InternalReturn::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+InternalReturn::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	out = in;
 	return true;
diff --git a/libs/ardour/internal_send.cc b/libs/ardour/internal_send.cc
index 26631d0fad..029a46ce53 100644
--- a/libs/ardour/internal_send.cc
+++ b/libs/ardour/internal_send.cc
@@ -284,7 +284,7 @@ InternalSend::connect_when_legal ()
 }
 
 bool
-InternalSend::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+InternalSend::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	out = in;
 	return true;
diff --git a/libs/ardour/lv2_plugin.cc b/libs/ardour/lv2_plugin.cc
index d44f9351c4..04012a7ada 100644
--- a/libs/ardour/lv2_plugin.cc
+++ b/libs/ardour/lv2_plugin.cc
@@ -971,7 +971,7 @@ LV2Plugin::find_presets()
 				                               lilv_node_as_string(name))));
 		} else {
 			warning << string_compose(
-			    _("Plugin \"%1\% preset \"%2%\" is missing a label\n"),
+			    _("Plugin \"%1\" preset \"%2\" is missing a label\n"),
 			    lilv_node_as_string(lilv_plugin_get_uri(_impl->plugin)),
 			    lilv_node_as_string(preset)) << endmsg;
 		}
diff --git a/libs/ardour/meter.cc b/libs/ardour/meter.cc
index 490b75dcb2..a7857f5859 100644
--- a/libs/ardour/meter.cc
+++ b/libs/ardour/meter.cc
@@ -165,7 +165,7 @@ PeakMeter::reset_max ()
 }
 
 bool
-PeakMeter::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+PeakMeter::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	out = in;
 	return true;
diff --git a/libs/ardour/monitor_processor.cc b/libs/ardour/monitor_processor.cc
index e55428b666..ed06647860 100644
--- a/libs/ardour/monitor_processor.cc
+++ b/libs/ardour/monitor_processor.cc
@@ -355,7 +355,7 @@ MonitorProcessor::configure_io (ChanCount in, ChanCount out)
 }
 
 bool
-MonitorProcessor::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+MonitorProcessor::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	out = in;
 	return true;
diff --git a/libs/ardour/plugin_insert.cc b/libs/ardour/plugin_insert.cc
index d519dbd7a7..b191cf4890 100644
--- a/libs/ardour/plugin_insert.cc
+++ b/libs/ardour/plugin_insert.cc
@@ -145,7 +145,7 @@ PluginInsert::output_streams() const
 		ChanCount out = info->n_outputs;
 		// DEBUG_TRACE (DEBUG::Processors, string_compose ("Plugin insert, static output streams = %1 for %2 plugins\n", out, _plugins.size()));
 		out.set_audio (out.n_audio() * _plugins.size());
-		out.set_midi (out.n_midi() * _plugins.size());
+		out.set_midi (out.n_midi() * _plugins.size() + midi_bypass.n_midi());
 		return out;
 	}
 }
@@ -465,7 +465,6 @@ PluginInsert::run (BufferSet& bufs, framepos_t /*start_frame*/, framepos_t /*end
 		}
 
 	} else {
-
 		if (has_no_audio_inputs()) {
 
 			/* silence all (audio) outputs. Should really declick
@@ -704,7 +703,7 @@ PluginInsert::configure_io (ChanCount in, ChanCount out)
  *  @return true if the given IO configuration can be supported.
  */
 bool
-PluginInsert::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+PluginInsert::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	return private_can_support_io_configuration (in, out).method != Impossible;
 }
@@ -714,9 +713,11 @@ PluginInsert::can_support_io_configuration (const ChanCount& in, ChanCount& out)
  *  it can be.
  */
 PluginInsert::Match
-PluginInsert::private_can_support_io_configuration (ChanCount const & in, ChanCount& out) const
+PluginInsert::private_can_support_io_configuration (ChanCount const & inx, ChanCount& out)
 {
 	PluginInfoPtr info = _plugins.front()->get_info();
+	ChanCount in; in += inx;
+	midi_bypass.reset();
 
 	if (info->reconfigurable_io()) {
 		/* Plugin has flexible I/O, so delegate to it */
@@ -731,6 +732,15 @@ PluginInsert::private_can_support_io_configuration (ChanCount const & in, ChanCo
 	ChanCount inputs  = info->n_inputs;
 	ChanCount outputs = info->n_outputs;
 
+	if (in.get(DataType::MIDI) == 1 && outputs.get(DataType::MIDI) == 0) {
+		DEBUG_TRACE ( DEBUG::Processors, string_compose ("bypassing midi-data around %1\n", name()));
+		midi_bypass.set(DataType::MIDI, 1);
+	}
+	if (in.get(DataType::MIDI) == 1 && inputs.get(DataType::MIDI) == 0) {
+		DEBUG_TRACE ( DEBUG::Processors, string_compose ("hiding midi-port from plugin %1\n", name()));
+		in.set(DataType::MIDI, 0);
+	}
+
 	bool no_inputs = true;
 	for (DataType::iterator t = DataType::begin(); t != DataType::end(); ++t) {
 		if (inputs.get (*t) != 0) {
@@ -741,13 +751,13 @@ PluginInsert::private_can_support_io_configuration (ChanCount const & in, ChanCo
 
 	if (no_inputs) {
 		/* no inputs so we can take any input configuration since we throw it away */
-		out = outputs;
+		out = outputs + midi_bypass;
 		return Match (NoInputs, 1);
 	}
 
 	/* Plugin inputs match requested inputs exactly */
 	if (inputs == in) {
-		out = outputs;
+		out = outputs + midi_bypass;
 		return Match (ExactMatch, 1);
 	}
 
@@ -789,6 +799,7 @@ PluginInsert::private_can_support_io_configuration (ChanCount const & in, ChanCo
 		for (DataType::iterator t = DataType::begin(); t != DataType::end(); ++t) {
 			out.set (*t, outputs.get(*t) * f);
 		}
+		out += midi_bypass;
 		return Match (Replicate, f);
 	}
 
@@ -812,7 +823,7 @@ PluginInsert::private_can_support_io_configuration (ChanCount const & in, ChanCo
 	}
 
 	if (can_split) {
-		out = outputs;
+		out = outputs + midi_bypass;
 		return Match (Split, 1);
 	}
 
@@ -836,10 +847,11 @@ PluginInsert::private_can_support_io_configuration (ChanCount const & in, ChanCo
 	}
 
 	if (could_hide && !cannot_hide) {
-		out = outputs;
+		out = outputs + midi_bypass;
 		return Match (Hide, 1, hide_channels);
 	}
 
+	midi_bypass.reset();
 	return Match (Impossible, 0);
 }
 
diff --git a/libs/ardour/port_insert.cc b/libs/ardour/port_insert.cc
index cf33f1b932..e7ff69040d 100644
--- a/libs/ardour/port_insert.cc
+++ b/libs/ardour/port_insert.cc
@@ -268,7 +268,7 @@ PortInsert::configure_io (ChanCount in, ChanCount out)
 }
 
 bool
-PortInsert::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+PortInsert::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	out = in;
 	return true;
diff --git a/libs/ardour/return.cc b/libs/ardour/return.cc
index 921be6a53a..4f9e8b958a 100644
--- a/libs/ardour/return.cc
+++ b/libs/ardour/return.cc
@@ -136,7 +136,7 @@ Return::run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pfra
 }
 
 bool
-Return::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+Return::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	out = in + _input->n_ports();
 	return true;
diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index 671a00319d..f53acebe14 100644
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -543,11 +543,10 @@ Route::process_output_buffers (BufferSet& bufs,
 			if (bufs.count() != (*i)->input_streams()) {
 				DEBUG_TRACE (
 					DEBUG::Processors, string_compose (
-						"%1 bufs = %2 input for %3 = %4\n",
+						"input port mismatch %1 bufs = %2 input for %3 = %4\n",
 						_name, bufs.count(), (*i)->name(), (*i)->input_streams()
 						)
 					);
-				continue;
 			}
 		}
 #endif
@@ -1656,7 +1655,8 @@ Route::try_configure_processors_unlocked (ChanCount in, ProcessorStreams* err)
 
 		if (boost::dynamic_pointer_cast<UnknownProcessor> (*p)) {
 			DEBUG_TRACE (DEBUG::Processors, "--- CONFIGURE ABORTED due to unknown processor.\n");
-			break;
+			DEBUG_TRACE (DEBUG::Processors, "}\n");
+			return list<pair<ChanCount, ChanCount> > ();
 		}
 
 		if ((*p)->can_support_io_configuration(in, out)) {
diff --git a/libs/ardour/send.cc b/libs/ardour/send.cc
index 107cf9862b..e74fd7f8ce 100644
--- a/libs/ardour/send.cc
+++ b/libs/ardour/send.cc
@@ -270,7 +270,7 @@ Send::set_state_2X (const XMLNode& node, int /* version */)
 }
 
 bool
-Send::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
+Send::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
 	/* sends have no impact at all on the channel configuration of the
 	   streams passing through the route. so, out == in.
diff --git a/libs/ardour/session_midi.cc b/libs/ardour/session_midi.cc
index e4fd58dedc..3e2a76b8d8 100644
--- a/libs/ardour/session_midi.cc
+++ b/libs/ardour/session_midi.cc
@@ -590,7 +590,7 @@ void
 Session::send_song_position_pointer (framepos_t t)
 {
 	if (midi_clock) {
-		midi_clock->position_changed (t);
+		/* Do nothing for the moment */
 	}
 }
 
diff --git a/libs/ardour/session_transport.cc b/libs/ardour/session_transport.cc
index b98a044d89..51d8d2c369 100644
--- a/libs/ardour/session_transport.cc
+++ b/libs/ardour/session_transport.cc
@@ -384,6 +384,7 @@ Session::butler_transport_work ()
 	g_atomic_int_dec_and_test (&_butler->should_do_transport_work);
 
 	DEBUG_TRACE (DEBUG::Transport, X_("Butler transport work all done\n"));
+	DEBUG_TRACE (DEBUG::Transport, X_(string_compose ("Frame %1\n", _transport_frame)));
 }
 
 void
@@ -1007,6 +1008,7 @@ Session::locate (framepos_t target_frame, bool with_roll, bool with_flush, bool
 		send_mmc_locate (_transport_frame);
 	}
 
+	_last_roll_location = _last_roll_or_reversal_location =  _transport_frame;
 	Located (); /* EMIT SIGNAL */
 }
 
diff --git a/libs/ardour/ticker.cc b/libs/ardour/ticker.cc
index 4f66128943..0a4081bec7 100644
--- a/libs/ardour/ticker.cc
+++ b/libs/ardour/ticker.cc
@@ -32,12 +32,80 @@
 #include "ardour/debug.h"
 
 using namespace ARDOUR;
+using namespace PBD;
+
+/** MIDI Clock Position tracking */
+class MidiClockTicker::Position : public Timecode::BBT_Time
+{
+public:
+
+	Position() : speed(0.0f), frame(0) { }
+	~Position() { }
+
+	/** Sync timing information taken from the given Session
+		@return True if timings differed */
+	bool sync (Session* s) {
+
+		bool didit = false;
+
+		double     sp = s->transport_speed();
+		framecnt_t fr = s->transport_frame();
+
+		if (speed != sp) {
+			speed = sp;
+			didit = true;
+		}
+
+		if (frame != fr) {
+			frame = fr;
+			didit = true;
+		}
+
+		/* Midi beats and clocks always gets updated for now */
+
+		s->bbt_time (this->frame, *this);
+
+		const TempoMap& tempo = s->tempo_map();
+
+		const double divisions   = tempo.meter_at(frame).divisions_per_bar();
+		const double divisor     = tempo.meter_at(frame).note_divisor();
+		const double qnote_scale = divisor * 0.25f;
+
+		/** Midi Beats in terms of Song Position Pointer is equivalent to total
+			sixteenth notes at 'time' */
+
+		midi_beats  = (((bars - 1) * divisions) + beats - 1);
+		midi_beats += (double)ticks / (double)Position::ticks_per_beat * qnote_scale;
+		midi_beats *= 16.0f / divisor;
+
+		midi_clocks = midi_beats * 6.0f;
+
+		return didit;
+	}
+
+	double      speed;
+	framecnt_t  frame;
+	double      midi_beats;
+	double      midi_clocks;
+
+	void print (std::ostream& s) {
+		s << "frames: " << frame << " midi beats: " << midi_beats << " speed: " << speed;
+	}
+};
+
 
 MidiClockTicker::MidiClockTicker ()
 	: _midi_port (0)
 	, _ppqn (24)
 	, _last_tick (0.0)
 {
+	_pos.reset (new Position());
+}
+
+MidiClockTicker::~MidiClockTicker()
+{
+	_midi_port = 0;
+	_pos.reset (0);
 }
 
 void
@@ -49,11 +117,53 @@ MidiClockTicker::set_session (Session* s)
 		 _session->TransportStateChange.connect_same_thread (_session_connections, boost::bind (&MidiClockTicker::transport_state_changed, this));
 		 _session->PositionChanged.connect_same_thread (_session_connections, boost::bind (&MidiClockTicker::position_changed, this, _1));
 		 _session->TransportLooped.connect_same_thread (_session_connections, boost::bind (&MidiClockTicker::transport_looped, this));
+		 _session->Located.connect_same_thread (_session_connections, boost::bind (&MidiClockTicker::session_located, this));
+
 		 update_midi_clock_port();
+		 _pos->sync (_session);
 	 }
 }
 
 void
+MidiClockTicker::session_located()
+{
+	DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Session Located: %1, speed: %2\n", _session->transport_frame(), _session->transport_speed()));
+
+	if (0 == _session || ! _pos->sync (_session)) {
+		return;
+	}
+
+	_last_tick = _pos->frame;
+
+	if (!Config->get_send_midi_clock()) {
+		return;
+	}
+
+	if (_pos->speed == 0.0f) {
+		uint32_t where = llrint (_pos->midi_beats);
+		send_position_event (where, 0);
+	} else if (_pos->speed == 1.0f) {
+#if 1
+		/* Experimental.  To really do this and have accuracy, the
+		   stop/locate/continue sequence would need queued to send immediately
+		   before the next midi clock. */
+
+		send_stop_event (0);
+
+		if (_pos->frame == 0) {
+			send_start_event (0);
+		} else {
+			uint32_t where = llrint (_pos->midi_beats);
+			send_position_event (where, 0);
+			send_continue_event (0);
+		}
+#endif
+	} else {
+		/* Varispeed not supported */
+	}
+}
+
+void
 MidiClockTicker::session_going_away ()
 {
 	SessionHandlePtr::session_going_away();
@@ -79,56 +189,61 @@ MidiClockTicker::transport_state_changed()
 		return;
 	}
 
-	float      speed    = _session->transport_speed();
-	framepos_t position = _session->transport_frame();
+	if (! _pos->sync (_session)) {
+		return;
+	}
 
-	DEBUG_TRACE (PBD::DEBUG::MidiClock,
-		 string_compose ("Transport state change @ %4, speed: %1 position: %2 play loop: %3\n", speed, position, _session->get_play_loop(), position)
+	DEBUG_TRACE (DEBUG::MidiClock,
+		 string_compose ("Transport state change @ %4, speed: %1 position: %2 play loop: %3\n",
+							_pos->speed, _pos->frame, _session->get_play_loop(), _pos->frame)
 	);
 
-	if (speed == 1.0f) {
-		_last_tick = position;
+	_last_tick = _pos->frame;
+
+	if (! Config->get_send_midi_clock()) {
+		return;
+	}
 
-		if (!Config->get_send_midi_clock())
-			return;
+	if (_pos->speed == 1.0f) {
 
 		if (_session->get_play_loop()) {
 			assert(_session->locations()->auto_loop_location());
-			if (position == _session->locations()->auto_loop_location()->start()) {
+
+			if (_pos->frame == _session->locations()->auto_loop_location()->start()) {
 				send_start_event(0);
 			} else {
 				send_continue_event(0);
 			}
-		} else if (position == 0) {
+
+		} else if (_pos->frame == 0) {
 			send_start_event(0);
 		} else {
 			send_continue_event(0);
 		}
 
-		send_midi_clock_event(0);
+		// send_midi_clock_event (0);
 
-	} else if (speed == 0.0f) {
-		if (!Config->get_send_midi_clock())
-			return;
-
-		send_stop_event(0);
-		send_position_event (position, 0);
+	} else if (_pos->speed == 0.0f) {
+		send_stop_event (0);
+		send_position_event (llrint (_pos->midi_beats), 0);
 	}
 
-	tick (position);
+	// tick (_pos->frame);
 }
 
 void
-MidiClockTicker::position_changed (framepos_t position)
+MidiClockTicker::position_changed (framepos_t)
 {
+#if 0
 	const double speed = _session->transport_speed();
-	DEBUG_TRACE (PBD::DEBUG::MidiClock, string_compose ("Transport Position Change: %1, speed: %2\n", position, speed));
+	DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Transport Position Change: %1, speed: %2\n", position, speed));
 
 	if (speed == 0.0f && Config->get_send_midi_clock()) {
 		send_position_event (position, 0);
 	}
 
 	_last_tick = position;
+#endif
 }
 
 void
@@ -137,7 +252,7 @@ MidiClockTicker::transport_looped()
 	Location* loop_location = _session->locations()->auto_loop_location();
 	assert(loop_location);
 
-	DEBUG_TRACE (PBD::DEBUG::MidiClock,
+	DEBUG_TRACE (DEBUG::MidiClock,
 		     string_compose ("Transport looped, position: %1, loop start: %2, loop end: %3, play loop: %4\n",
 				     _session->transport_frame(), loop_location->start(), loop_location->end(), _session->get_play_loop())
 		);
@@ -155,23 +270,28 @@ MidiClockTicker::transport_looped()
 }
 
 void
-MidiClockTicker::tick (const framepos_t& transport_frame)
+MidiClockTicker::tick (const framepos_t& /* transport_frame */)
 {
 	if (!Config->get_send_midi_clock() || _session == 0 || _session->transport_speed() != 1.0f || _midi_port == 0) {
 		return;
 	}
 
+	MIDI::JackMIDIPort* mp = dynamic_cast<MIDI::JackMIDIPort*> (_midi_port);
+	if (! mp) {
+		return;
+	}
+
+	const framepos_t end = _pos->frame + mp->nframes_this_cycle();
+	double iter = _last_tick;
+
 	while (true) {
-		double next_tick = _last_tick + one_ppqn_in_frames (transport_frame);
-		frameoffset_t next_tick_offset = llrint (next_tick) - transport_frame;
+		double clock_delta = one_ppqn_in_frames (llrint (iter));
+		double next_tick   = iter + clock_delta;
+		frameoffset_t next_tick_offset = llrint (next_tick) - end;
 
-		MIDI::JackMIDIPort* mp = dynamic_cast<MIDI::JackMIDIPort*> (_midi_port);
-		
-		/*
-		DEBUG_TRACE (PBD::DEBUG::MidiClock,
-			     string_compose ("Transport: %1, last tick time: %2, next tick time: %3, offset: %4, cycle length: %5\n",
-					     transport_frame, _last_tick, next_tick, next_tick_offset, mp ? mp->nframes_this_cycle() : 0));
-		*/
+		DEBUG_TRACE (DEBUG::MidiClock,
+				 string_compose ("Tick: iter: %1, last tick time: %2, next tick time: %3, offset: %4, cycle length: %5\n",
+						 iter, _last_tick, next_tick, next_tick_offset, mp ? mp->nframes_this_cycle() : 0));
 
 		if (!mp || (next_tick_offset >= mp->nframes_this_cycle())) {
 			break;
@@ -181,10 +301,14 @@ MidiClockTicker::tick (const framepos_t& transport_frame)
 			send_midi_clock_event (next_tick_offset);
 		}
 
-		_last_tick = next_tick;
+		iter = next_tick;
 	}
+
+	_last_tick  = iter;
+	_pos->frame = end;
 }
 
+
 double
 MidiClockTicker::one_ppqn_in_frames (framepos_t transport_position)
 {
@@ -204,7 +328,7 @@ MidiClockTicker::send_midi_clock_event (pframes_t offset)
 		return;
 	}
 
-	// DEBUG_TRACE (PBD::DEBUG::MidiClock, string_compose ("Tick with offset %1\n", offset));
+	DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Tick with offset %1\n", offset));
 
 	static uint8_t _midi_clock_tick[1] = { MIDI_CMD_COMMON_CLOCK };
 	_midi_port->write (_midi_clock_tick, 1, offset);
@@ -217,7 +341,7 @@ MidiClockTicker::send_start_event (pframes_t offset)
 		return;
 	}
 
-	DEBUG_TRACE (PBD::DEBUG::MidiClock, string_compose ("Start %1\n", _last_tick));
+	DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Start %1\n", _last_tick));
 
 	static uint8_t _midi_clock_tick[1] = { MIDI_CMD_COMMON_START };
 	_midi_port->write (_midi_clock_tick, 1, offset);
@@ -230,7 +354,7 @@ MidiClockTicker::send_continue_event (pframes_t offset)
 		return;
 	}
 
-	DEBUG_TRACE (PBD::DEBUG::MidiClock, string_compose ("Continue %1\n", _last_tick));
+	DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Continue %1\n", _last_tick));
 
 	static uint8_t _midi_clock_tick[1] = { MIDI_CMD_COMMON_CONTINUE };
 	_midi_port->write (_midi_clock_tick, 1, offset);
@@ -243,29 +367,19 @@ MidiClockTicker::send_stop_event (pframes_t offset)
 		return;
 	}
 
-	DEBUG_TRACE (PBD::DEBUG::MidiClock, string_compose ("Stop %1\n", _last_tick));
+	DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Stop %1\n", _last_tick));
 
 	static uint8_t _midi_clock_tick[1] = { MIDI_CMD_COMMON_STOP };
 	_midi_port->write (_midi_clock_tick, 1, offset);
 }
 
 void
-MidiClockTicker::send_position_event (framepos_t transport_position, pframes_t offset)
+MidiClockTicker::send_position_event (uint32_t midi_beats, pframes_t offset)
 {
-	if (_midi_port == 0 || _session == 0 || _session->engine().freewheeling()) {
+	if (!_midi_port) {
 		return;
 	}
 
-	const TempoMap& tempo = _session->tempo_map();
-
-	Timecode::BBT_Time time;
-	_session->bbt_time (transport_position, time);
-	const double beats_per_bar = tempo.meter_at(transport_position).divisions_per_bar();
-
-	/* Midi Beats in terms of Song Position Pointer is equivalent to total
-	   sixteenth notes at 'time' */
-	const uint32_t midi_beats = 4 * (((time.bars - 1) * beats_per_bar) + time.beats - 1);
-
 	/* can only use 14bits worth */
 	if (midi_beats > 0x3fff) {
 		return;
@@ -278,7 +392,7 @@ MidiClockTicker::send_position_event (framepos_t transport_position, pframes_t o
 		midi_beats & 0x3f80
 	};
 
-	DEBUG_TRACE (PBD::DEBUG::MidiClock, string_compose ("Song Position: %1\n", midi_beats));
-
 	_midi_port->midimsg (msg, sizeof (msg), offset);
+
+	DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Song Position Sent: %1\n", midi_beats));
 }
diff --git a/libs/pbd/cocoa_open_uri.mm b/libs/pbd/cocoa_open_uri.mm
index 2c6822ac94..90a3995d71 100644
--- a/libs/pbd/cocoa_open_uri.mm
+++ b/libs/pbd/cocoa_open_uri.mm
@@ -1,6 +1,7 @@
 #include <CoreFoundation/CFLocale.h>
 #import  <CoreFoundation/CFString.h>
 #import  <Foundation/NSString.h>
+#import  <Foundation/NSURL.h>
 #import  <Foundation/NSAutoreleasePool.h>
 #import  <AppKit/NSWorkspace.h>
 
diff --git a/libs/pbd/wscript b/libs/pbd/wscript
index e26b96ca11..6907dd7693 100644
--- a/libs/pbd/wscript
+++ b/libs/pbd/wscript
@@ -132,12 +132,13 @@ def build(bld):
     obj.uselib       = 'GLIBMM SIGCPP XML UUID SNDFILE GIOMM'
     if sys.platform == 'darwin':
         TaskGen.task_gen.mappings['.mm'] = TaskGen.task_gen.mappings['.cc']
-        obj.source += [ 'cocoa_open_uri.mm' ]
+        if 'cocoa_open_uri.mm' not in obj.source:
+            obj.source += [ 'cocoa_open_uri.mm' ]
         obj.uselib += ' OSX'
     obj.vnum         = LIBPBD_LIB_VERSION
     obj.install_path = os.path.join(bld.env['LIBDIR'], 'ardour3')
     obj.defines     = ['PACKAGE="' + I18N_PACKAGE + '"']
-
+    
     if bld.env['build_target'] == 'x86_64':
         obj.defines += [ 'USE_X86_64_ASM' ]