Merged with trunk, and a few trivial GUI updates etc.

git-svn-id: svn://localhost/ardour2/branches/midi@664 d708f5d6-7413-0410-9779-e7cbd77b26cf

24 files changed, 240 insertions, 219 deletions

diff --git a/libs/ardour/SConscript b/libs/ardour/SConscript
index c42728f85b..c93a7c4593 100644
--- a/libs/ardour/SConscript
+++ b/libs/ardour/SConscript
@@ -106,7 +106,7 @@ arch_specific_objects = [ ]
 
 osc_files = [ 'osc.cc' ]
 vst_files = [ 'vst_plugin.cc', 'session_vst.cc' ]
-coreaudio_files = [ 'coreaudio_source.cc' ]
+coreaudio_files = [ 'coreaudiosource.cc' ]
 extra_sources = [ ]
 
 if ardour['VST']:
@@ -206,7 +206,7 @@ ardour.Merge ([
 	     libraries['lrdf'],
 	     libraries['samplerate'],
 	     libraries['sigc2'],
-	     libraries['pbd3'],
+	     libraries['pbd'],
 	     libraries['soundtouch'],
 	     libraries['midi++2'],
 	     libraries['glib2'],
diff --git a/libs/ardour/ardour/audiofilesource.h b/libs/ardour/ardour/audiofilesource.h
index ecbac569d5..36251c07ff 100644
--- a/libs/ardour/ardour/audiofilesource.h
+++ b/libs/ardour/ardour/audiofilesource.h
@@ -42,7 +42,7 @@ class AudioFileSource : public AudioSource {
 		Removable = 0x8,
 		RemovableIfEmpty = 0x10,
 		RemoveAtDestroy = 0x20,
-		BuildPeaks = 0x40
+		NoPeakFile = 0x40
 	};
 
 	virtual ~AudioFileSource ();
@@ -62,7 +62,7 @@ class AudioFileSource : public AudioSource {
 	   cannot.
 	 */
 
-	static AudioFileSource* create (string path_plus_channel);
+	static AudioFileSource* create (const string& path_plus_channel, Flag flags = Flag (0));
 	static AudioFileSource* create (const XMLNode&);
 
 	static bool get_soundfile_info (string path, SoundFileInfo& _info, string& error);
@@ -97,7 +97,7 @@ class AudioFileSource : public AudioSource {
 	static void set_search_path (string);
 	static void set_header_position_offset (jack_nframes_t offset, bool negative);
 
-	static sigc::signal<void,struct tm*, time_t> HeaderPositionOffsetChanged;
+	static sigc::signal<void> HeaderPositionOffsetChanged;
 
 	XMLNode& get_state ();
 	int set_state (const XMLNode&);
@@ -107,7 +107,7 @@ class AudioFileSource : public AudioSource {
 	   to cause issues.
 	*/
 
-	void handle_header_position_change (struct tm*, time_t tnow);
+	void handle_header_position_change ();
 
   protected:
 	
diff --git a/libs/ardour/ardour/coreaudio_source.h b/libs/ardour/ardour/coreaudiosource.h
index 81f1a14050..ba9f122fc9 100644
--- a/libs/ardour/ardour/coreaudio_source.h
+++ b/libs/ardour/ardour/coreaudiosource.h
@@ -27,15 +27,22 @@ namespace ARDOUR {
 
 class CoreAudioSource : public AudioFileSource {
   public:
-	CoreAudioSource (const string& path_plus_channel, bool build_peak = true);
 	CoreAudioSource (const XMLNode&);
+	CoreAudioSource (const string& path_plus_channel, Flag);
 	~CoreAudioSource ();
 
 	float sample_rate() const;
 	int update_header (jack_nframes_t when, struct tm&, time_t);
 
+	int flush_header () {return 0;};
+	void set_header_timeline_position () {};
+
   protected:
 	jack_nframes_t read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const;
+	
+	jack_nframes_t write_unlocked (Sample *dst, jack_nframes_t cnt, char * workbuf) 
+	{ return 0; }
+	
 
   private:
 	ExtAudioFileRef af;
@@ -45,7 +52,7 @@ class CoreAudioSource : public AudioFileSource {
 	mutable jack_nframes_t tmpbufsize;
 	mutable Glib::Mutex _tmpbuf_lock;
 
-	void init (const string &str, bool build_peak);
+	void init (const string &str);
 };
 
 }; /* namespace ARDOUR */
diff --git a/libs/ardour/ardour/destructive_filesource.h b/libs/ardour/ardour/destructive_filesource.h
index c92a0762ee..2d10528ac8 100644
--- a/libs/ardour/ardour/destructive_filesource.h
+++ b/libs/ardour/ardour/destructive_filesource.h
@@ -32,8 +32,7 @@ namespace ARDOUR {
 class DestructiveFileSource : public SndFileSource {
   public:
 	DestructiveFileSource (std::string path, SampleFormat samp_format, HeaderFormat hdr_format, jack_nframes_t rate,
-			       Flag flags = AudioFileSource::Flag (AudioFileSource::Writable|
-								   AudioFileSource::BuildPeaks));
+			       Flag flags = AudioFileSource::Flag (AudioFileSource::Writable));
 
 	DestructiveFileSource (const XMLNode&);
 	~DestructiveFileSource ();
diff --git a/libs/ardour/ardour/diskstream.h b/libs/ardour/ardour/diskstream.h
index f43e8273a7..a72289acd1 100644
--- a/libs/ardour/ardour/diskstream.h
+++ b/libs/ardour/ardour/diskstream.h
@@ -80,6 +80,9 @@ class Diskstream : public Stateful, public sigc::trackable
 	void unref() { if (_refcnt) _refcnt--; if (_refcnt == 0) delete this; }
 	uint32_t refcnt() const { return _refcnt; }
 
+	virtual float playback_buffer_load() const = 0;
+	virtual float capture_buffer_load() const = 0;
+
 	void set_flag (Flag f)   { _flags |= f; }
 	void unset_flag (Flag f) { _flags &= ~f; }
 
@@ -106,6 +109,7 @@ class Diskstream : public Stateful, public sigc::trackable
 	virtual void punch_out() {}
 
 	virtual void set_speed (double);
+	virtual void non_realtime_set_speed () = 0;
 
 	virtual Playlist *playlist () = 0;
 	virtual int use_new_playlist () = 0;
@@ -128,6 +132,9 @@ class Diskstream : public Stateful, public sigc::trackable
 	/* Stateful */
 	virtual XMLNode& get_state(void) = 0;
 	virtual int      set_state(const XMLNode& node) = 0;
+	
+	// FIXME: makes sense for all diskstream types?
+	virtual void monitor_input (bool) {}
 
 	jack_nframes_t capture_offset() const { return _capture_offset; }
 	virtual void   set_capture_offset ();
@@ -166,7 +173,7 @@ class Diskstream : public Stateful, public sigc::trackable
 	virtual void set_pending_overwrite (bool) = 0;
 	virtual int  overwrite_existing_buffers () = 0;
 	virtual void reverse_scrub_buffer (bool to_forward) = 0;
-	//void set_block_size (jack_nframes_t);
+	virtual void set_block_size (jack_nframes_t) = 0;
 	virtual int  internal_playback_seek (jack_nframes_t distance) = 0;
 	virtual int  can_internal_playback_seek (jack_nframes_t distance) = 0;
 	virtual int  rename_write_sources () = 0;
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 6284e94900..0e1b7627be 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -68,6 +68,7 @@ class AuxInput;
 class Source;
 class AudioSource;
 
+class Diskstream;
 class AudioDiskstream;
 class AudioFileSource;
 class Auditioner;
@@ -281,30 +282,25 @@ class Session : public sigc::trackable, public Stateful
 	void refill_all_diskstream_buffers ();
 	uint32_t diskstream_buffer_size() const { return dstream_buffer_size; }
 	
-	/* XXX fix required here when we get new diskstream types *, but
-	   not sure of the direction to take this in until then.
-	*/
-
-	uint32_t get_next_diskstream_id() const { return n_audio_diskstreams(); }
-	uint32_t n_audio_diskstreams() const;
+	uint32_t get_next_diskstream_id() const { return n_diskstreams(); }
+	uint32_t n_diskstreams() const;
 	
-	typedef list<AudioDiskstream *> AudioDiskstreamList;
+	template<class T> void foreach_diskstream (T *obj, void (T::*func)(Diskstream&));
 
-	Session::AudioDiskstreamList audio_disk_streams() const {
+	typedef list<Diskstream *> DiskstreamList;
+	
+	Session::DiskstreamList disk_streams() const {
 		Glib::RWLock::ReaderLock lm (diskstream_lock);
-		return audio_diskstreams; /* XXX yes, force a copy */
+		return diskstreams; /* XXX yes, force a copy */
 	}
 
-	void foreach_audio_diskstream (void (AudioDiskstream::*func)(void));
-	template<class T> void foreach_audio_diskstream (T *obj, void (T::*func)(AudioDiskstream&));
-
 	typedef list<Route *> RouteList;
-
+	
 	RouteList get_routes() const {
 		Glib::RWLock::ReaderLock rlock (route_lock);
 		return routes; /* XXX yes, force a copy */
 	}
-
+	
 	uint32_t nroutes() const { return routes.size(); }
 	uint32_t ntracks () const;
 	uint32_t nbusses () const;
@@ -719,8 +715,6 @@ class Session : public sigc::trackable, public Stateful
 	sigc::signal<void,Playlist*> PlaylistAdded;
 	sigc::signal<void,Playlist*> PlaylistRemoved;
 
-	Playlist *get_playlist (string name);
-
 	uint32_t n_playlists() const;
 
 	template<class T> void foreach_playlist (T *obj, void (T::*func)(Playlist *));
@@ -980,7 +974,7 @@ class Session : public sigc::trackable, public Stateful
 	void set_frame_rate (jack_nframes_t nframes);
 
   protected:
-	friend class AudioDiskstream;
+	friend class Diskstream;
 	void stop_butler ();
 	void wait_till_butler_finished();
 
@@ -1475,7 +1469,7 @@ class Session : public sigc::trackable, public Stateful
 
 	/* disk-streams */
 
-	AudioDiskstreamList  audio_diskstreams; 
+	DiskstreamList  diskstreams; 
 	mutable Glib::RWLock diskstream_lock;
 	uint32_t dstream_buffer_size;
 	void add_diskstream (Diskstream*);
diff --git a/libs/ardour/ardour/session_diskstream.h b/libs/ardour/ardour/session_diskstream.h
index 33fc5419ba..52db157f44 100644
--- a/libs/ardour/ardour/session_diskstream.h
+++ b/libs/ardour/ardour/session_diskstream.h
@@ -27,10 +27,10 @@
 namespace ARDOUR {
 
 template<class T> void 
-Session::foreach_audio_diskstream (T *obj, void (T::*func)(AudioDiskstream&)) 
+Session::foreach_diskstream (T *obj, void (T::*func)(Diskstream&)) 
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); i++) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); i++) {
 		if (!(*i)->hidden()) {
 			(obj->*func) (**i);
 		}
diff --git a/libs/ardour/ardour/sndfilesource.h b/libs/ardour/ardour/sndfilesource.h
index d146bb5793..5e3c1f621d 100644
--- a/libs/ardour/ardour/sndfilesource.h
+++ b/libs/ardour/ardour/sndfilesource.h
@@ -39,8 +39,7 @@ class SndFileSource : public AudioFileSource {
 		       Flag flags = AudioFileSource::Flag (AudioFileSource::Writable|
 							   AudioFileSource::Removable|
 							   AudioFileSource::RemovableIfEmpty|
-							   AudioFileSource::CanRename|
-							   AudioFileSource::BuildPeaks));
+							   AudioFileSource::CanRename));
 		       
 	/* constructor to be called for existing in-session files */
 	
@@ -52,7 +51,7 @@ class SndFileSource : public AudioFileSource {
 	int update_header (jack_nframes_t when, struct tm&, time_t);
 	int flush_header ();
 
-	static Flag default_in_session_flags();
+	void handle_smpte_offset_change (jack_nframes_t offset, bool negative);
 
   protected:
 	void set_header_timeline_position ();
diff --git a/libs/ardour/audio_diskstream.cc b/libs/ardour/audio_diskstream.cc
index 277fad0ae8..f24993b87b 100644
--- a/libs/ardour/audio_diskstream.cc
+++ b/libs/ardour/audio_diskstream.cc
@@ -55,10 +55,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-//sigc::signal<void,AudioDiskstream*>    AudioDiskstream::AudioDiskstreamCreated;
 sigc::signal<void,list<AudioFileSource*>*> AudioDiskstream::DeleteSources;
-//sigc::signal<void>                AudioDiskstream::DiskOverrun;
-//sigc::signal<void>                AudioDiskstream::DiskUnderrun;
 
 AudioDiskstream::AudioDiskstream (Session &sess, const string &name, Diskstream::Flag flag)
 	: Diskstream(sess, name, flag)
@@ -295,9 +292,9 @@ AudioDiskstream::find_and_use_playlist (const string& name)
 	Playlist* pl;
 	AudioPlaylist* playlist;
 		
-	if ((pl = _session.get_playlist (name)) == 0) {
-		error << string_compose(_("AudioDiskstream: Session doesn't know about a Playlist called \"%1\""), name) << endmsg;
-		return -1;
+	if ((pl = _session.playlist_by_name (name)) == 0) {
+		playlist = new AudioPlaylist(_session, name);
+		pl = playlist;
 	}
 
 	if ((playlist = dynamic_cast<AudioPlaylist*> (pl)) == 0) {
@@ -1630,6 +1627,7 @@ AudioDiskstream::transport_stopped (struct tm& when, time_t twhen, bool abort_ca
 			srcs.push_back (s);
 
 			if ((fsrc = dynamic_cast<AudioFileSource *>(s)) != 0) {
+				cerr << "updating source after capture\n";
 				fsrc->update_header (capture_info.front()->start, when, twhen);
 			}
 
diff --git a/libs/ardour/audio_playlist.cc b/libs/ardour/audio_playlist.cc
index be5c9ab5d9..aa8940dce4 100644
--- a/libs/ardour/audio_playlist.cc
+++ b/libs/ardour/audio_playlist.cc
@@ -20,7 +20,7 @@
 
 #include <algorithm>
 
-#include <stdlib.h>
+#include <cstdlib>
 
 #include <sigc++/bind.h>
 
diff --git a/libs/ardour/audio_track.cc b/libs/ardour/audio_track.cc
index 0f22ebbe44..82a2a38c2c 100644
--- a/libs/ardour/audio_track.cc
+++ b/libs/ardour/audio_track.cc
@@ -94,14 +94,6 @@ AudioTrack::~AudioTrack ()
 	}
 }
 
-#if 0
-void
-AudioTrack::handle_smpte_offset_change ()
-{
-	diskstream
-}
-#endif
-
 int
 AudioTrack::deprecated_use_diskstream_connections ()
 {
diff --git a/libs/ardour/audiofilesource.cc b/libs/ardour/audiofilesource.cc
index 1e13a29acc..0663f5f9b1 100644
--- a/libs/ardour/audiofilesource.cc
+++ b/libs/ardour/audiofilesource.cc
@@ -42,7 +42,7 @@
 // if these headers come before sigc++ is included
 // the parser throws ObjC++ errors. (nil is a keyword)
 #ifdef HAVE_COREAUDIO 
-#include <ardour/coreaudio_source.h>
+#include <ardour/coreaudiosource.h>
 #include <AudioToolbox/ExtendedAudioFile.h>
 #include <AudioToolbox/AudioFormat.h>
 #endif // HAVE_COREAUDIO
@@ -55,9 +55,9 @@ using namespace PBD;
 string AudioFileSource::peak_dir = "";
 string AudioFileSource::search_path;
 
-sigc::signal<void,struct tm*, time_t> AudioFileSource::HeaderPositionOffsetChanged;
-bool                                  AudioFileSource::header_position_negative;
-uint64_t                              AudioFileSource::header_position_offset;
+sigc::signal<void> AudioFileSource::HeaderPositionOffsetChanged;
+bool               AudioFileSource::header_position_negative;
+uint64_t           AudioFileSource::header_position_offset;
 
 char   AudioFileSource::bwf_country_code[3] = "US";
 char   AudioFileSource::bwf_organization_code[4] = "LAS";
@@ -122,7 +122,6 @@ AudioFileSource::init (string pathstr, bool must_exist)
 	next_peak_clear_should_notify = false;
 	
 	if (!find (pathstr, must_exist, is_new)) {
-		cerr << "cannot find " << pathstr << " with me = " << must_exist << endl;
 		return -1;
 	}
 
@@ -211,16 +210,16 @@ AudioFileSource::create (const XMLNode& node)
 
 #ifdef HAVE_COREAUDIO
 AudioFileSource*
-AudioFileSource::create (const string& idstr)
+AudioFileSource::create (const string& idstr, Flag flags)
 {
 	AudioFileSource* es = 0;
 
 	try {
-		es = new CoreAudioSource (idstr);
+		es = new CoreAudioSource (idstr, flags);
 	}
 
 	catch (failed_constructor& err) {
-		es = new SndFileSource (idstr);
+		es = new SndFileSource (idstr, flags);
 	}
 
 	return es;
@@ -229,9 +228,9 @@ AudioFileSource::create (const string& idstr)
 #else
 
 AudioFileSource*
-AudioFileSource::create (string idstr)
+AudioFileSource::create (const string& idstr, Flag flags)
 {
-	return new SndFileSource (idstr);
+	return new SndFileSource (idstr, flags);
 }
 
 #endif // HAVE_COREAUDIO
@@ -595,33 +594,28 @@ AudioFileSource::set_search_path (string p)
 void
 AudioFileSource::set_header_position_offset (jack_nframes_t offset, bool negative)
 {
-	time_t tnow;
-
-	time (&tnow);
-
 	header_position_offset = offset;
 	header_position_negative = negative;
-	HeaderPositionOffsetChanged (localtime (&tnow), tnow); /* EMIT SIGNAL */
-}
 
-void
-AudioFileSource::set_timeline_position (jack_nframes_t pos)
-{
-	timeline_position = pos;
+	HeaderPositionOffsetChanged ();
 }
 
-void
-AudioFileSource::handle_header_position_change (struct tm* now, time_t tnow)
+void 
+AudioFileSource::handle_header_position_change ()
 {
-	/* don't do this if the file has never had its header flushed to disk yet */
-
-	if (writable() && _timestamp) {
+	if (writable()) {
 		set_header_timeline_position ();
 		flush_header ();
 	}
 }
 
 void
+AudioFileSource::set_timeline_position (jack_nframes_t pos)
+{
+	timeline_position = pos;
+}
+
+void
 AudioFileSource::set_allow_remove_if_empty (bool yn)
 {
 	if (writable()) {
@@ -655,8 +649,14 @@ AudioFileSource::set_name (string newname, bool destructive)
 bool
 AudioFileSource::is_empty (string path)
 {
-	/* XXX fix me */
+	bool ret = false;
+	AudioFileSource* afs = create (path, NoPeakFile);
 
-	return false;
+	if (afs) {
+		ret = (afs->length() == 0);
+		delete afs;
+	}
+
+	return ret;
 }
 
diff --git a/libs/ardour/coreaudio_source.cc b/libs/ardour/coreaudiosource.cc
index 1b0ee565e7..55409a8524 100644
--- a/libs/ardour/coreaudio_source.cc
+++ b/libs/ardour/coreaudiosource.cc
@@ -18,8 +18,7 @@
 */
 
 #include <pbd/error.h>
-
-#include <ardour/coreaudio_source.h>
+#include <ardour/coreaudiosource.h>
 
 #include "i18n.h"
 
@@ -31,22 +30,21 @@ using namespace PBD;
 CoreAudioSource::CoreAudioSource (const XMLNode& node)
 	: AudioFileSource (node)
 {
-	init (_name, true);
+	init (_name);
+	
 	AudioSourceCreated (this); /* EMIT SIGNAL */
 }
 
-CoreAudioSource::CoreAudioSource (const string& idstr, bool build_peak)
-	: AudioFileSource(idstr, build_peak)
+CoreAudioSource::CoreAudioSource (const string& idstr, Flag flags)
+	: AudioFileSource(idstr, flags)
 {
-	init (idstr, build_peak);
+	init (idstr);
 
-	if (build_peak) {
-		 AudioSourceCreated (this); /* EMIT SIGNAL */
-	}
+	AudioSourceCreated (this); /* EMIT SIGNAL */
 }
 
 void 
-CoreAudioSource::init (const string& idstr, bool build_peak)
+CoreAudioSource::init (const string& idstr)
 {
 	string::size_type pos;
 	string file;
@@ -132,7 +130,7 @@ CoreAudioSource::init (const string& idstr, bool build_peak)
 		throw failed_constructor ();
 	}
 	
-	if (build_peak) {
+	if (_build_peakfiles) {
 		if (initialize_peakfile (false, file)) {
 			error << "initialize peakfile failed" << endmsg;
 			ExtAudioFileDispose (af);
@@ -155,7 +153,7 @@ CoreAudioSource::~CoreAudioSource ()
 }
 
 jack_nframes_t
-CoreAudioSource::read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const
+CoreAudioSource::read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const
 {
 	OSStatus err = noErr;
 
diff --git a/libs/ardour/midi_diskstream.cc b/libs/ardour/midi_diskstream.cc
index 0af4af4f7c..fdf9092308 100644
--- a/libs/ardour/midi_diskstream.cc
+++ b/libs/ardour/midi_diskstream.cc
@@ -55,10 +55,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-//sigc::signal<void,MidiDiskstream*>    MidiDiskstream::MidiDiskstreamCreated;
 sigc::signal<void,list<SMFSource*>*> MidiDiskstream::DeleteSources;
-//sigc::signal<void>                MidiDiskstream::DiskOverrun;
-//sigc::signal<void>                MidiDiskstream::DiskUnderrun;
 
 MidiDiskstream::MidiDiskstream (Session &sess, const string &name, Diskstream::Flag flag)
 	: Diskstream(sess, name, flag)
@@ -154,13 +151,13 @@ MidiDiskstream::find_and_use_playlist (const string& name)
 	Playlist* pl;
 	MidiPlaylist* playlist;
 		
-	if ((pl = _session.get_playlist (name)) == 0) {
-		error << string_compose(_("MidiDiskstream: Session doesn't know about a Playlist called \"%1\""), name) << endmsg;
-		return -1;
+	if ((pl = _session.playlist_by_name (name)) == 0) {
+		playlist = new MidiPlaylist(_session, name);
+		pl = playlist;
 	}
 
 	if ((playlist = dynamic_cast<MidiPlaylist*> (pl)) == 0) {
-		error << string_compose(_("MidiDiskstream: Playlist \"%1\" isn't an midi playlist"), name) << endmsg;
+		error << string_compose(_("MidiDiskstream: Playlist \"%1\" isn't a midi playlist"), name) << endmsg;
 		return -1;
 	}
 
diff --git a/libs/ardour/midi_track.cc b/libs/ardour/midi_track.cc
index d4f7be1e6f..4a9febcdca 100644
--- a/libs/ardour/midi_track.cc
+++ b/libs/ardour/midi_track.cc
@@ -186,32 +186,30 @@ MidiTrack::set_diskstream (MidiDiskstream& ds, void *src)
 int 
 MidiTrack::use_diskstream (string name)
 {
-	/*
 	MidiDiskstream *dstream;
 
-	if ((dstream = _session.diskstream_by_name (name)) == 0) {
+	if ((dstream = dynamic_cast<MidiDiskstream*>(_session.diskstream_by_name (name))) == 0) {
 	  PBD::error << string_compose(_("MidiTrack: diskstream \"%1\" not known by session"), name) << endmsg;
 		return -1;
 	}
 
 	return set_diskstream (*dstream, this);
-	*/
+	
 	return 0;
 }
 
 int 
 MidiTrack::use_diskstream (id_t id)
 {
-	/*
 	MidiDiskstream *dstream;
 
-	if ((dstream = _session.diskstream_by_id (id)) == 0) {
+	if ((dstream = dynamic_cast<MidiDiskstream*>(_session.diskstream_by_id (id))) == 0) {
 	  	PBD::error << string_compose(_("MidiTrack: diskstream \"%1\" not known by session"), id) << endmsg;
 		return -1;
 	}
 	
 	return set_diskstream (*dstream, this);
-	*/
+	
 	return 0;
 }
 
diff --git a/libs/ardour/plugin.cc b/libs/ardour/plugin.cc
index 2d1f8ffcbd..9fc6c57909 100644
--- a/libs/ardour/plugin.cc
+++ b/libs/ardour/plugin.cc
@@ -127,10 +127,16 @@ Plugin::MIDIPortControl::set_value (float value)
 			value = 0.0;
 		}
 	} else {
-		value = lower + (range * value);
-		
-		if (logarithmic) {
-			value = exp(value);
+
+		if (!logarithmic) {
+			value = lower + (range * value);
+		} else {
+			float _lower = 0.0f;
+			if (lower > 0.0f) {
+				_lower = log(lower);
+			}
+
+			value = exp(_lower + log(range) * value);
 		}
 	}
 
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index c6c6f0444c..2fcd09a31c 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -462,10 +462,10 @@ Session::~Session ()
 	}
 
 #ifdef TRACK_DESTRUCTION
-	cerr << "delete audio_diskstreams\n";
+	cerr << "delete diskstreams\n";
 #endif /* TRACK_DESTRUCTION */
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ) {
-		AudioDiskstreamList::iterator tmp;
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ) {
+		DiskstreamList::iterator tmp;
 
 		tmp = i;
 		++tmp;
@@ -973,7 +973,7 @@ Session::set_auto_input (bool yn)
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+			for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (!auto_input);   
@@ -991,7 +991,7 @@ Session::reset_input_monitor_state ()
 {
 	if (transport_rolling()) {
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if ((*i)->record_enabled ()) {
 				//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
 				(*i)->monitor_input (Config->get_use_hardware_monitoring() && !auto_input);
@@ -999,7 +999,7 @@ Session::reset_input_monitor_state ()
 		}
 	} else {
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if ((*i)->record_enabled ()) {
 				//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
 				(*i)->monitor_input (Config->get_use_hardware_monitoring());
@@ -1080,7 +1080,7 @@ Session::auto_loop_changed (Location* location)
 		}
 		else if (seamless_loop && !loop_changing) {
 			
-			// schedule a locate-roll to refill the audio_diskstreams at the
+			// schedule a locate-roll to refill the diskstreams at the
 			// previous loop end
 			loop_changing = true;
 
@@ -1277,7 +1277,7 @@ Session::enable_record ()
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			
-			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+			for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					(*i)->monitor_input (true);   
 				}
@@ -1316,7 +1316,7 @@ Session::disable_record (bool rt_context, bool force)
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			
-			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+			for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					(*i)->monitor_input (false);   
 				}
@@ -1343,7 +1343,7 @@ Session::step_back_from_record ()
 		*/
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		        if (auto_input && (*i)->record_enabled ()) {
 			        //cerr << "switching from input" << __FILE__ << __LINE__ << endl << endl;
 		                (*i)->monitor_input (false);   
@@ -1512,7 +1512,7 @@ Session::set_block_size (jack_nframes_t nframes)
 			(*i)->set_block_size (nframes);
 		}
 		
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			(*i)->set_block_size (nframes);
 		}
 
@@ -2115,21 +2115,14 @@ Session::add_route (Route* route)
 }
 
 void
-Session::add_diskstream (Diskstream* s)
+Session::add_diskstream (Diskstream* dstream)
 {
-	// FIXME: temporary.  duh.
-	AudioDiskstream* dstream = dynamic_cast<AudioDiskstream*>(s);
-	if (!dstream) {
-		cerr << "FIXME: Non Audio Diskstream" << endl;
-		return;
-	}
-
 	/* need to do this in case we're rolling at the time, to prevent false underruns */
 	dstream->non_realtime_do_refill();
 	
 	{ 
 		Glib::RWLock::WriterLock lm (diskstream_lock);
-		audio_diskstreams.push_back (dstream);
+		diskstreams.push_back (dstream);
 	}
 
 	/* take a reference to the diskstream, preventing it from
@@ -2194,7 +2187,7 @@ Session::remove_route (Route& route)
 
 		{
 			Glib::RWLock::WriterLock lm (diskstream_lock);
-			audio_diskstreams.remove (ds);
+			diskstreams.remove (ds);
 		}
 
 		ds->unref ();
@@ -2483,7 +2476,7 @@ Session::get_maximum_extent () const
 	   ensure atomicity.
 	*/
 
-	for (AudioDiskstreamList::const_iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::const_iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		Playlist* pl = (*i)->playlist();
 		if ((me = pl->get_maximum_extent()) > max) {
 			max = me;
@@ -2499,7 +2492,7 @@ Session::diskstream_by_name (string name)
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
 	// FIXME: duh
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if ((*i)->name() == name) {
 			return* i;
 		}
@@ -2514,7 +2507,7 @@ Session::diskstream_by_id (id_t id)
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
 	// FIXME: duh
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if ((*i)->id() == id) {
 			return *i;
 		}
@@ -2840,7 +2833,7 @@ Session::remove_last_capture ()
 
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 	
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		list<Region*>& l = (*i)->last_capture_regions();
 		
 		if (!l.empty()) {
@@ -3152,18 +3145,6 @@ Session::create_audio_source_for_session (AudioDiskstream& ds, uint32_t chan, bo
 /* Playlist management */
 
 Playlist *
-Session::get_playlist (string name)
-{
-	Playlist* ret = 0;
-
-	if ((ret = playlist_by_name (name)) == 0) {
-		ret = new AudioPlaylist (*this, name);
-	}
-
-	return ret;
-}
-
-Playlist *
 Session::playlist_by_name (string name)
 {
 	Glib::Mutex::Lock lm (playlist_lock);
@@ -3385,29 +3366,30 @@ Session::set_all_mute (bool yn)
 }
 		
 uint32_t
-Session::n_audio_diskstreams () const
+Session::n_diskstreams () const
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 	uint32_t n = 0;
 
-	for (AudioDiskstreamList::const_iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::const_iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if (!(*i)->hidden()) {
 			n++;
 		}
 	}
 	return n;
 }
-
+/*
 void 
 Session::foreach_audio_diskstream (void (AudioDiskstream::*func)(void)) 
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if (!(*i)->hidden()) {
 			((*i)->*func)();
 		}
 	}
 }
+*/
 
 void
 Session::graph_reordered ()
@@ -3429,7 +3411,7 @@ Session::graph_reordered ()
 	   reflect any changes in latencies within the graph.
 	*/
 	
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->set_capture_offset ();
 	}
 }
@@ -3712,7 +3694,7 @@ Session::reset_native_file_format ()
 	//RWLockMonitor lm1 (route_lock, true, __LINE__, __FILE__);
 	Glib::RWLock::ReaderLock lm2 (diskstream_lock);
 
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->reset_write_sources (false);
 	}
 }
diff --git a/libs/ardour/session_butler.cc b/libs/ardour/session_butler.cc
index b1451912d0..f0a2af0a83 100644
--- a/libs/ardour/session_butler.cc
+++ b/libs/ardour/session_butler.cc
@@ -168,7 +168,7 @@ Session::butler_thread_work ()
 	struct timeval begin, end;
 	struct pollfd pfd[1];
 	bool disk_work_outstanding = false;
-	AudioDiskstreamList::iterator i;
+	DiskstreamList::iterator i;
 
 	butler_mixdown_buffer = new Sample[AudioDiskstream::disk_io_frames()];
 	butler_gain_buffer = new gain_t[AudioDiskstream::disk_io_frames()];
@@ -239,7 +239,7 @@ Session::butler_thread_work ()
 			}
 		}
 
-		//for (i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		//for (i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			// cerr << "BEFORE " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 		//}
 
@@ -255,15 +255,17 @@ Session::butler_thread_work ()
 
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		
-		for (i = audio_diskstreams.begin(); !transport_work_requested() && butler_should_run && i != audio_diskstreams.end(); ++i) {
+		for (i = diskstreams.begin(); !transport_work_requested() && butler_should_run && i != diskstreams.end(); ++i) {
 			// cerr << "rah fondr " << (*i)->io()->name () << endl;
+			AudioDiskstream* ads = dynamic_cast<AudioDiskstream*>(*i);
+			if (!ads) continue; // FIXME
 
-			switch ((*i)->do_refill (butler_mixdown_buffer, butler_gain_buffer, conv_buffer)) {
+			switch (ads->do_refill (butler_mixdown_buffer, butler_gain_buffer, conv_buffer)) {
 			case 0:
-				bytes += (*i)->read_data_count();
+				bytes += ads->read_data_count();
 				break;
 			case 1:
-				bytes += (*i)->read_data_count();
+				bytes += ads->read_data_count();
 				disk_work_outstanding = true;
 				break;
 				
@@ -275,7 +277,7 @@ Session::butler_thread_work ()
 
 		}
 
-		if (i != audio_diskstreams.end()) {
+		if (i != diskstreams.end()) {
 			/* we didn't get to all the streams */
 			disk_work_outstanding = true;
 		}
@@ -297,7 +299,7 @@ Session::butler_thread_work ()
 		compute_io = true;
 		gettimeofday (&begin, 0);
 
-		for (i = audio_diskstreams.begin(); !transport_work_requested() && butler_should_run && i != audio_diskstreams.end(); ++i) {
+		for (i = diskstreams.begin(); !transport_work_requested() && butler_should_run && i != diskstreams.end(); ++i) {
 			// cerr << "write behind for " << (*i)->name () << endl;
 			
 			switch ((*i)->do_flush (conv_buffer)) {
@@ -326,7 +328,7 @@ Session::butler_thread_work ()
 			request_stop ();
 		}
 
-		if (i != audio_diskstreams.end()) {
+		if (i != diskstreams.end()) {
 			/* we didn't get to all the streams */
 			disk_work_outstanding = true;
 		}
@@ -353,7 +355,7 @@ Session::butler_thread_work ()
 			Glib::Mutex::Lock lm (butler_request_lock);
 
 			if (butler_should_run && (disk_work_outstanding || transport_work_requested())) {
-//				for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+//				for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 //					cerr << "AFTER " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 //				}
 
@@ -393,7 +395,7 @@ Session::overwrite_some_buffers (Diskstream* ds)
 	} else {
 
 		Glib::RWLock::ReaderLock dm (diskstream_lock);
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			(*i)->set_pending_overwrite (true);
 		}
 	}
diff --git a/libs/ardour/session_export.cc b/libs/ardour/session_export.cc
index ddced9cc5f..37365c8403 100644
--- a/libs/ardour/session_export.cc
+++ b/libs/ardour/session_export.cc
@@ -495,7 +495,7 @@ Session::prepare_to_export (AudioExportSpecification& spec)
 
 	{
 		Glib::RWLock::ReaderLock lm (diskstream_lock);
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if ((*i)-> seek (spec.start_frame, true)) {
 				error << string_compose (_("%1: cannot seek to %2 for export"),
 						  (*i)->name(), spec.start_frame)
diff --git a/libs/ardour/session_process.cc b/libs/ardour/session_process.cc
index 23e7757c9d..9e3809f6b8 100644
--- a/libs/ardour/session_process.cc
+++ b/libs/ardour/session_process.cc
@@ -74,7 +74,7 @@ Session::process (jack_nframes_t nframes)
 void
 Session::prepare_diskstreams ()
 {
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->prepare ();
 	}
 }
@@ -151,7 +151,7 @@ Session::process_routes (jack_nframes_t nframes, jack_nframes_t offset)
 			   call path, so make sure we release any outstanding locks here before we return failure.
 			*/
 
-			for (AudioDiskstreamList::iterator ids = audio_diskstreams.begin(); ids != audio_diskstreams.end(); ++ids) {
+			for (DiskstreamList::iterator ids = diskstreams.begin(); ids != diskstreams.end(); ++ids) {
 				(*ids)->recover ();
 			}
 
@@ -190,7 +190,7 @@ Session::silent_process_routes (jack_nframes_t nframes, jack_nframes_t offset)
 			   call path, so make sure we release any outstanding locks here before we return failure.
 			*/
 
-			for (AudioDiskstreamList::iterator ids = audio_diskstreams.begin(); ids != audio_diskstreams.end(); ++ids) {
+			for (DiskstreamList::iterator ids = diskstreams.begin(); ids != diskstreams.end(); ++ids) {
 				(*ids)->recover ();
 			}
 
@@ -209,7 +209,7 @@ Session::commit_diskstreams (jack_nframes_t nframes, bool &needs_butler)
 	float pworst = 1.0f;
 	float cworst = 1.0f;
 
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 
 		if ((*i)->hidden()) {
 			continue;
@@ -579,7 +579,7 @@ Session::follow_slave (jack_nframes_t nframes, jack_nframes_t offset)
 				bool ok = true;
 				jack_nframes_t frame_delta = slave_transport_frame - _transport_frame;
 				
-				for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+				for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 					if (!(*i)->can_internal_playback_seek (frame_delta)) {
 						ok = false;
 						break;
@@ -587,7 +587,7 @@ Session::follow_slave (jack_nframes_t nframes, jack_nframes_t offset)
 				}
 
 				if (ok) {
-					for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+					for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 						(*i)->internal_playback_seek (frame_delta);
 					}
 					_transport_frame += frame_delta;
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 12092b1bad..9f21eb5c4e 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -59,6 +59,7 @@
 #include <ardour/configuration.h>
 #include <ardour/session.h>
 #include <ardour/audio_diskstream.h>
+#include <ardour/midi_diskstream.h>
 #include <ardour/utils.h>
 #include <ardour/audioplaylist.h>
 #include <ardour/audiofilesource.h>
@@ -270,7 +271,7 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	AudioSource::AudioSourceCreated.connect (mem_fun (*this, &Session::add_audio_source));
 	Playlist::PlaylistCreated.connect (mem_fun (*this, &Session::add_playlist));
 	Redirect::RedirectCreated.connect (mem_fun (*this, &Session::add_redirect));
-	AudioDiskstream::DiskstreamCreated.connect (mem_fun (*this, &Session::add_diskstream));
+	Diskstream::DiskstreamCreated.connect (mem_fun (*this, &Session::add_diskstream));
 	NamedSelection::NamedSelectionCreated.connect (mem_fun (*this, &Session::add_named_selection));
 
 	IO::MoreOutputs.connect (mem_fun (*this, &Session::ensure_passthru_buffers));
@@ -624,12 +625,16 @@ Session::load_diskstreams (const XMLNode& node)
 	clist = node.children();
 
 	for (citer = clist.begin(); citer != clist.end(); ++citer) {
-		
-		AudioDiskstream* dstream;
+		Diskstream* dstream = NULL;
 
 		try {
-			dstream = new AudioDiskstream (*this, **citer);
-			/* added automatically by AudioDiskstreamCreated handler */
+			if ((*citer)->name() == "AudioDiskstream") {
+				dstream = new AudioDiskstream (*this, **citer);
+				/* added automatically by DiskstreamCreated handler */
+			} else {
+				assert((*citer)->name() == "MidiDiskstream");
+				dstream = new MidiDiskstream (*this, **citer);
+			}
 		} 
 		
 		catch (failed_constructor& err) {
@@ -1380,7 +1385,7 @@ Session::state(bool full_state)
 
 	{ 
 		Glib::RWLock::ReaderLock dl (diskstream_lock);
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				child->add_child_nocopy ((*i)->get_state());
 			}
diff --git a/libs/ardour/session_time.cc b/libs/ardour/session_time.cc
index 0db3afcee6..494a78ae88 100644
--- a/libs/ardour/session_time.cc
+++ b/libs/ardour/session_time.cc
@@ -113,7 +113,6 @@ Session::set_smpte_offset_negative (bool neg)
 	SMPTEOffsetChanged (); /* EMIT SIGNAL */
 }
 
-
 void
 Session::smpte_to_sample( SMPTE::Time& smpte, jack_nframes_t& sample, bool use_offset, bool use_subframes ) const
 {
diff --git a/libs/ardour/session_transport.cc b/libs/ardour/session_transport.cc
index d7ab60f3fb..6a92d71d1c 100644
--- a/libs/ardour/session_transport.cc
+++ b/libs/ardour/session_transport.cc
@@ -206,7 +206,7 @@ Session::butler_transport_work ()
 	}
 
 	if (post_transport_work & PostTransportInputChange) {
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			(*i)->non_realtime_input_change ();
 		}
 	}
@@ -222,7 +222,7 @@ Session::butler_transport_work ()
 		cumulative_rf_motion = 0;
 		reset_rf_scale (0);
 
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				if ((*i)->speed() != 1.0f || (*i)->speed() != -1.0f) {
 					(*i)->seek ((jack_nframes_t) (_transport_frame * (double) (*i)->speed()));
@@ -254,7 +254,7 @@ Session::non_realtime_set_speed ()
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->non_realtime_set_speed ();
 	}
 }
@@ -264,7 +264,7 @@ Session::non_realtime_overwrite ()
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if ((*i)->pending_overwrite) {
 			(*i)->overwrite_existing_buffers ();
 		}
@@ -280,7 +280,7 @@ Session::non_realtime_stop (bool abort)
 	
 	did_record = false;
 	
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if ((*i)->get_captured_frames () != 0) {
 			did_record = true;
 			break;
@@ -333,7 +333,7 @@ Session::non_realtime_stop (bool abort)
 		_have_captured = true;
 	}
 
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->transport_stopped (*now, xnow, abort);
 	}
 	
@@ -370,7 +370,7 @@ Session::non_realtime_stop (bool abort)
 	}
 #endif
 
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				if ((*i)->speed() != 1.0f || (*i)->speed() != -1.0f) {
 					(*i)->seek ((jack_nframes_t) (_transport_frame * (double) (*i)->speed()));
@@ -494,7 +494,7 @@ Session::set_auto_loop (bool yn)
 
 			if (seamless_loop) {
 				// set all diskstreams to use internal looping
-				for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+				for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 					if (!(*i)->hidden()) {
 						(*i)->set_loop (loc);
 					}
@@ -502,7 +502,7 @@ Session::set_auto_loop (bool yn)
 			}
 			else {
 				// set all diskstreams to NOT use internal looping
-				for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+				for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 					if (!(*i)->hidden()) {
 						(*i)->set_loop (0);
 					}
@@ -532,7 +532,7 @@ Session::set_auto_loop (bool yn)
 		clear_events (Event::AutoLoop);
 
 		// set all diskstreams to NOT use internal looping
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				(*i)->set_loop (0);
 			}
@@ -653,7 +653,7 @@ Session::locate (jack_nframes_t target_frame, bool with_roll, bool with_flush, b
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+			for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching from input" << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (!auto_input);
@@ -668,7 +668,7 @@ Session::locate (jack_nframes_t target_frame, bool with_roll, bool with_flush, b
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+			for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input" << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (true);
@@ -714,7 +714,7 @@ Session::set_transport_speed (float speed, bool abort)
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+			for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input" << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (true);	
@@ -740,7 +740,7 @@ Session::set_transport_speed (float speed, bool abort)
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+			for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if (auto_input && (*i)->record_enabled ()) {
 					//cerr << "switching from input" << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (false);	
@@ -791,7 +791,7 @@ Session::set_transport_speed (float speed, bool abort)
 		_last_transport_speed = _transport_speed;
 		_transport_speed = speed;
 		
-		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+		for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if ((*i)->realtime_set_speed ((*i)->speed(), true)) {
 				post_transport_work = PostTransportWork (post_transport_work | PostTransportSpeed);
 			}
@@ -881,7 +881,7 @@ Session::actually_start_transport ()
 	transport_sub_state |= PendingDeclickIn;
 	_transport_speed = 1.0;
 	
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->realtime_set_speed ((*i)->speed(), true);
 	}
 
@@ -1014,7 +1014,7 @@ Session::set_slave_source (SlaveSource src, jack_nframes_t frame)
 	
 	_slave_type = src;
 
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if (!(*i)->hidden()) {
 			if ((*i)->realtime_set_speed ((*i)->speed(), true)) {
 				non_rt_required = true;
@@ -1242,7 +1242,7 @@ Session::update_latency_compensation (bool with_stop, bool abort)
 	/* reflect any changes in latencies into capture offsets
 	*/
 	
-	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
+	for (DiskstreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->set_capture_offset ();
 	}
 }
diff --git a/libs/ardour/sndfilesource.cc b/libs/ardour/sndfilesource.cc
index 24a70f636b..443a24e3c2 100644
--- a/libs/ardour/sndfilesource.cc
+++ b/libs/ardour/sndfilesource.cc
@@ -55,6 +55,7 @@ SndFileSource::SndFileSource (const XMLNode& node)
 }
 
 SndFileSource::SndFileSource (string idstr, Flag flags)
+	                                /* files created this way are never writable or removable */
 	: AudioFileSource (idstr, Flag (flags & ~(Writable|Removable|RemovableIfEmpty|RemoveAtDestroy)))
 {
 	init (idstr);
@@ -63,7 +64,7 @@ SndFileSource::SndFileSource (string idstr, Flag flags)
 		throw failed_constructor ();
 	}
 
-	if (_build_peakfiles) {
+	if (!(_flags & NoPeakFile) && _build_peakfiles) {
 		if (initialize_peakfile (false, _path)) {
 			sf_close (sf);
 			sf = 0;
@@ -170,9 +171,10 @@ SndFileSource::SndFileSource (string idstr, SampleFormat sfmt, HeaderFormat hf,
 			delete _broadcast_info;
 			_broadcast_info = 0;
 		}
+		
 	}
 	
-	if (_build_peakfiles) {
+	if (!(_flags & NoPeakFile) && _build_peakfiles) {
 		if (initialize_peakfile (true, _path)) {
 			sf_close (sf);
 			sf = 0;
@@ -180,12 +182,6 @@ SndFileSource::SndFileSource (string idstr, SampleFormat sfmt, HeaderFormat hf,
 		}
 	}
 
-	/* since SndFileSource's constructed with this constructor can be writable, make sure we update if the header info changes */
-
-	if (writable()) {
-		HeaderPositionOffsetChanged.connect (mem_fun (*this, &AudioFileSource::handle_header_position_change));
-	}
-
 	AudioSourceCreated (this); /* EMIT SIGNAL */
 }
 
@@ -235,34 +231,56 @@ SndFileSource::open ()
 
 	_length = _info.frames;
 
+
+	_broadcast_info = (SF_BROADCAST_INFO*) calloc (1, sizeof (SF_BROADCAST_INFO));
+	
+	/* lookup broadcast info */
+	
+	if (sf_command (sf, SFC_GET_BROADCAST_INFO, _broadcast_info, sizeof (*_broadcast_info)) != SF_TRUE) {
+
+		/* if the file has data but no broadcast info, then clearly, there is no broadcast info */
+
+		if (_length) {
+			free (_broadcast_info);
+			_broadcast_info = 0;
+			_flags = Flag (_flags & ~Broadcast);
+		}
+
+	} else {
+	
+		/* XXX 64 bit alert: when JACK switches to a 64 bit frame count, this needs to use the high bits
+		   of the time reference.
+		*/
+		
+		set_timeline_position (_broadcast_info->time_reference_low);
+	}
+
 	if (writable()) {
 		sf_command (sf, SFC_SET_UPDATE_HEADER_AUTO, 0, SF_FALSE);
+
+		/* update header if header offset info changes */
+		
+		AudioFileSource::HeaderPositionOffsetChanged.connect (mem_fun (*this, &AudioFileSource::handle_header_position_change));
 	}
 
 	return 0;
 }
 
-void
-SndFileSource::close ()
+SndFileSource::~SndFileSource ()
 {
+	GoingAway (this); /* EMIT SIGNAL */
+
 	if (sf) {
 		sf_close (sf);
 		sf = 0;
 	}
-}
-
-SndFileSource::~SndFileSource ()
-{
-	GoingAway (this); /* EMIT SIGNAL */
-
-	close ();
 
 	if (interleave_buf) {
 		delete [] interleave_buf;
 	}
 
 	if (_broadcast_info) {
-		delete [] _broadcast_info;
+		free (_broadcast_info);
 	}
 }
 
@@ -404,27 +422,38 @@ SndFileSource::write_unlocked (Sample *data, jack_nframes_t cnt, char * workbuf)
 int
 SndFileSource::update_header (jack_nframes_t when, struct tm& now, time_t tnow)
 {	
-	/* allow derived classes to override how this is done */
-
 	set_timeline_position (when);
 
 	if (_flags & Broadcast) {
-		/* this will flush the header implicitly */
-		return setup_broadcast_info (when, now, tnow);
-	} else {
-		return flush_header ();
-	}
+		if (setup_broadcast_info (when, now, tnow)) {
+			return -1;
+		}
+	} 
+
+	return flush_header ();
 }
 
 int
 SndFileSource::flush_header ()
 {
+	if (!writable() || (sf == 0)) {
+		return -1;
+	}
+
 	return (sf_command (sf, SFC_UPDATE_HEADER_NOW, 0, 0) != SF_TRUE);
 }
 
 int
 SndFileSource::setup_broadcast_info (jack_nframes_t when, struct tm& now, time_t tnow)
 {
+	if (!writable()) {
+		return -1;
+	}
+
+	if (!(_flags & Broadcast)) {
+		return 0;
+	}
+
 	/* random code is 9 digits */
 	
 	int random_code = random() % 999999999;
@@ -452,12 +481,10 @@ SndFileSource::setup_broadcast_info (jack_nframes_t when, struct tm& now, time_t
 	
 	set_header_timeline_position ();
 
-	/* note that libsndfile flushes the header to disk when resetting the broadcast info */
-
 	if (sf_command (sf, SFC_SET_BROADCAST_INFO, _broadcast_info, sizeof (*_broadcast_info)) != SF_TRUE) {
 		error << string_compose (_("cannot set broadcast info for audio file %1; Dropping broadcast info for this file"), _path) << endmsg;
 		_flags = Flag (_flags & ~Broadcast);
-		delete _broadcast_info;
+		free (_broadcast_info);
 		_broadcast_info = 0;
 		return -1;
 	}
@@ -470,6 +497,10 @@ SndFileSource::set_header_timeline_position ()
 {
 	uint64_t pos;
 
+	if (!(_flags & Broadcast)) {
+		return;
+	}
+
 	_broadcast_info->time_reference_high = 0;
 
 	if (header_position_negative) {
@@ -491,6 +522,13 @@ SndFileSource::set_header_timeline_position ()
 
 	_broadcast_info->time_reference_high = (pos >> 32);
 	_broadcast_info->time_reference_low = (pos & 0xffffffff);
+
+	if (sf_command (sf, SFC_SET_BROADCAST_INFO, _broadcast_info, sizeof (*_broadcast_info)) != SF_TRUE) {
+		error << string_compose (_("cannot set broadcast info for audio file %1; Dropping broadcast info for this file"), _path) << endmsg;
+		_flags = Flag (_flags & ~Broadcast);
+		free (_broadcast_info);
+		_broadcast_info = 0;
+	}
 }
 
 jack_nframes_t