diff --git a/gtk2_ardour/engine_dialog.cc b/gtk2_ardour/engine_dialog.cc
index 37c29f4187..d438ff8327 100644
--- a/gtk2_ardour/engine_dialog.cc
+++ b/gtk2_ardour/engine_dialog.cc
@@ -87,7 +87,6 @@ EngineControl::EngineControl ()
 	, midi_refresh_button (_("Refresh list"))
 	, ignore_changes (0)
 	, _desired_sample_rate (0)
-	, no_push (true)
 	, started_at_least_once (false)
 {
 	using namespace Notebook_Helpers;
@@ -290,8 +289,6 @@ EngineControl::EngineControl ()
 	output_channels.signal_changed().connect (sigc::mem_fun (*this, &EngineControl::parameter_changed));
 
 	notebook.signal_switch_page().connect (sigc::mem_fun (*this, &EngineControl::on_switch_page));
-
-	no_push = false;
  }
 
  void
@@ -874,10 +871,6 @@ EngineControl::EngineControl ()
 	 /* pick up any saved state for this device */
 
 	 maybe_display_saved_state ();
-
-	 /* and push it to the backend */
-
-	 push_state_to_backend (false);
  }	
 
  string
@@ -1207,14 +1200,9 @@ EngineControl::EngineControl ()
 	 }
  }
 
-
  int
  EngineControl::push_state_to_backend (bool start)
  {
-	 if (no_push) {
-		 return 0;
-	 }
-
 	 boost::shared_ptr<ARDOUR::AudioBackend> backend = ARDOUR::AudioEngine::instance()->current_backend();
 
 	 if (!backend) {
diff --git a/gtk2_ardour/engine_dialog.h b/gtk2_ardour/engine_dialog.h
index 31648b6dbb..6d10eb76ac 100644
--- a/gtk2_ardour/engine_dialog.h
+++ b/gtk2_ardour/engine_dialog.h
@@ -114,7 +114,6 @@ class EngineControl : public ArdourDialog, public PBD::ScopedConnectionList {
     
     uint32_t ignore_changes;
     uint32_t _desired_sample_rate;
-    bool     no_push;
     bool     started_at_least_once;
 
     void driver_changed ();
diff --git a/gtk2_ardour/wscript b/gtk2_ardour/wscript
index a4ec9deee8..97677bc5fc 100644
--- a/gtk2_ardour/wscript
+++ b/gtk2_ardour/wscript
@@ -379,12 +379,13 @@ def build(bld):
                 ../libs/fst/vstwin.c
                 ../vst/winmain.c
         '''
-        obj.uselib = 'ALSA'
         obj.use          = [ 'libpbd',
                              'libmidipp',
                              'libtaglib',
                              'libardour',
                              'libardour_cp',
+                             'libtimecode',
+                             'libmidipp',
                              'libgtk2_ardour',
                              'libgtkmm2ext',
                              'libtaglib']
@@ -407,21 +408,22 @@ def build(bld):
         obj.source    = gtk2_ardour_sources
         obj.target = 'ardour-' + bld.env['VERSION']
         obj.includes = ['.']
+        obj.use      = [ 'libpbd',
+                         'libardour',
+                         'libardour_cp',
+                         'libtimecode',
+                         'libmidipp',
+                         'libgtk2_ardour',
+                         'libgtkmm2ext',
+                       ]
 
     # continue with setup of obj, which could be a shared library
     # or an executable.
 
     obj.install_path = os.path.join(bld.env['LIBDIR'], 'ardour3')
-
-    obj.uselib       = 'UUID FLAC FONTCONFIG GLIBMM GTHREAD GTK OGG ALSA CURL DL'
+    obj.uselib       = 'UUID FLAC FONTCONFIG GLIBMM GTHREAD GTK OGG CURL DL'
     obj.uselib       += ' GTKMM GNOMECANVASMM GNOMECANVAS FFTW3F'
     obj.uselib       += ' AUDIOUNITS OSX GTKOSX LO '
-    obj.use          = [ 'libpbd',
-                         'libmidipp',
-                         'ardour',
-                         'libardour_cp',
-                         'libgtkmm2ext',
-                         ]
 
     if bld.env['build_target'] == 'mingw':
 	if bld.env['DEBUG'] == False:
diff --git a/libs/ardour/ardour/audio_buffer.h b/libs/ardour/ardour/audio_buffer.h
index 42aba607f9..054a1f7b45 100644
--- a/libs/ardour/ardour/audio_buffer.h
+++ b/libs/ardour/ardour/audio_buffer.h
@@ -207,7 +207,7 @@ public:
 		return _data + offset;
 	}
 
-    bool check_silence (pframes_t, pframes_t&) const;
+        bool check_silence (pframes_t, pframes_t&) const;
 
 	void prepare () { _written = false; _silent = false; }
 	bool written() const { return _written; }
diff --git a/libs/ardour/ardour/buffer.h b/libs/ardour/ardour/buffer.h
index cbb92e7c4a..4570a7a663 100644
--- a/libs/ardour/ardour/buffer.h
+++ b/libs/ardour/ardour/buffer.h
@@ -80,8 +80,8 @@ public:
 	virtual void merge_from (const Buffer& src, framecnt_t len, framecnt_t dst_offset = 0, framecnt_t src_offset = 0) = 0;
 
   protected:
-	Buffer(DataType type, size_t capacity)
-		: _type(type), _capacity(capacity), _size(0), _silent(true)
+	Buffer(DataType type)
+		: _type(type), _capacity(0), _size(0), _silent (true)
 	{}
 
 	DataType  _type;
diff --git a/libs/ardour/audio_buffer.cc b/libs/ardour/audio_buffer.cc
index 1fd0337dd1..a36ad81c2a 100644
--- a/libs/ardour/audio_buffer.cc
+++ b/libs/ardour/audio_buffer.cc
@@ -28,15 +28,15 @@ using namespace PBD;
 using namespace ARDOUR;
 
 AudioBuffer::AudioBuffer(size_t capacity)
-	: Buffer(DataType::AUDIO, capacity)
+	: Buffer (DataType::AUDIO)
 	, _owns_data (false)
 	, _data (0)
 {
-	if (_capacity > 0) {
+	if (capacity) {
 		_owns_data = true; // prevent resize() from gagging
-		resize (_capacity);
+		resize (capacity);
 		_silent = false; // force silence on the intial buffer state
-		silence (_capacity);
+		clear ();
 	}
 }
 
@@ -50,21 +50,29 @@ void
 AudioBuffer::resize (size_t size)
 {
 	if (!_owns_data) {
+		/* XXX how the hell is this enforced? */
+		_capacity = size;
 		return;
 	}
 
-	if (size < _capacity) {
-		_size = size;
+	if (_data && size < _capacity) {
+		/* buffer is already large enough */
+		
+		if (size < _size) {
+			/* truncate */
+			_size = size;
+		}
+
 		return;
 	}
 
 	free (_data);
 
-	_capacity = size;
-	_size = size;
-	_silent = false;
+	cache_aligned_malloc ((void**) &_data, sizeof (Sample) * size);
 
-	cache_aligned_malloc ((void**) &_data, sizeof (Sample) * _capacity);
+	_capacity = size;
+	_size = 0;
+	_silent = false;
 }
 
 bool
diff --git a/libs/ardour/audio_port.cc b/libs/ardour/audio_port.cc
index 6a86360b69..2fecbf9392 100644
--- a/libs/ardour/audio_port.cc
+++ b/libs/ardour/audio_port.cc
@@ -56,14 +56,11 @@ AudioPort::cycle_start (pframes_t nframes)
 }
 
 void
-AudioPort::cycle_end (pframes_t)
+AudioPort::cycle_end (pframes_t nframes)
 {
         if (sends_output() && !_buffer->written()) {
-                /* we can't use nframes here because the current buffer capacity may
-                   be shorter than the full buffer size if we split the cycle.
-                */
-		if (_buffer->capacity () > 0) {
-			_buffer->silence (_buffer->capacity());
+		if (_buffer->capacity() >= nframes) {
+			_buffer->silence (nframes);
 		}
 	}
 }
diff --git a/libs/ardour/buffer_set.cc b/libs/ardour/buffer_set.cc
index e67aee6be7..227d7a1e95 100644
--- a/libs/ardour/buffer_set.cc
+++ b/libs/ardour/buffer_set.cc
@@ -167,7 +167,7 @@ BufferSet::ensure_buffers(DataType type, size_t num_buffers, size_t buffer_capac
 	// If there's not enough or they're too small, just nuke the whole thing and
 	// rebuild it (so I'm lazy..)
 	if (bufs.size() < num_buffers
-			|| (bufs.size() > 0 && bufs[0]->capacity() < buffer_capacity)) {
+	    || (bufs.size() > 0 && bufs[0]->capacity() < buffer_capacity)) {
 
 		// Nuke it
 		for (BufferVec::iterator i = bufs.begin(); i != bufs.end(); ++i) {
@@ -179,7 +179,7 @@ BufferSet::ensure_buffers(DataType type, size_t num_buffers, size_t buffer_capac
 		for (size_t i = 0; i < num_buffers; ++i) {
 			bufs.push_back(Buffer::create(type, buffer_capacity));
 		}
-
+		
 		_available.set(type, num_buffers);
 		_count.set (type, num_buffers);
 	}
diff --git a/libs/ardour/midi_buffer.cc b/libs/ardour/midi_buffer.cc
index d75b861ea1..1a6cb7fa26 100644
--- a/libs/ardour/midi_buffer.cc
+++ b/libs/ardour/midi_buffer.cc
@@ -33,12 +33,12 @@ using namespace PBD;
 
 // FIXME: mirroring for MIDI buffers?
 MidiBuffer::MidiBuffer(size_t capacity)
-	: Buffer(DataType::MIDI, capacity)
-	, _data(0)
+	: Buffer (DataType::MIDI)
+	, _data (0)
 {
 	if (capacity) {
-		resize(_capacity);
-		silence(_capacity);
+		resize (capacity);
+		silence (capacity);
 	}
 }
 
@@ -50,17 +50,22 @@ MidiBuffer::~MidiBuffer()
 void
 MidiBuffer::resize(size_t size)
 {
-	assert(size > 0);
+	if (_data && size < _capacity) {
+
+		if (_size < size) {
+			/* truncate */
+			_size = size;
+		}
 
-	if (size < _capacity) {
 		return;
 	}
 
-	free(_data);
+	free (_data);
+
+	cache_aligned_malloc ((void**) &_data, size);
 
 	_size = 0;
 	_capacity = size;
-	cache_aligned_malloc ((void**) &_data, _capacity);
 
 	assert(_data);
 }
diff --git a/libs/ardour/thread_buffers.cc b/libs/ardour/thread_buffers.cc
index fd3160bb15..e469187ce9 100644
--- a/libs/ardour/thread_buffers.cc
+++ b/libs/ardour/thread_buffers.cc
@@ -60,7 +60,7 @@ ThreadBuffers::ensure_buffers (ChanCount howmany)
 
 	for (DataType::iterator t = DataType::begin(); t != DataType::end(); ++t) {
 		size_t count = std::max (scratch_buffers->available().get(*t), howmany.get(*t));
-		size_t size = _engine->raw_buffer_size (*t);
+		size_t size = _engine->raw_buffer_size (*t) / sizeof (Sample);
 
 		scratch_buffers->ensure_buffers (*t, count, size);
 		mix_buffers->ensure_buffers (*t, count, size);
@@ -68,12 +68,14 @@ ThreadBuffers::ensure_buffers (ChanCount howmany)
 		route_buffers->ensure_buffers (*t, count, size);
 	}
 
-	delete [] gain_automation_buffer;
-	gain_automation_buffer = new gain_t[_engine->raw_buffer_size (DataType::AUDIO)];
-	delete [] send_gain_automation_buffer;
-	send_gain_automation_buffer = new gain_t[_engine->raw_buffer_size (DataType::AUDIO)];
+	size_t audio_buffer_size = _engine->raw_buffer_size (DataType::AUDIO) / sizeof (Sample);
 
-	allocate_pan_automation_buffers (_engine->raw_buffer_size (DataType::AUDIO), howmany.n_audio(), false);
+	delete [] gain_automation_buffer;
+	gain_automation_buffer = new gain_t[audio_buffer_size];
+	delete [] send_gain_automation_buffer;
+	send_gain_automation_buffer = new gain_t[audio_buffer_size];
+
+	allocate_pan_automation_buffers (audio_buffer_size, howmany.n_audio(), false);
 }
 
 void
diff --git a/libs/backends/jack/jack_audiobackend.cc b/libs/backends/jack/jack_audiobackend.cc
index 332b6eec85..8df97a1e30 100644
--- a/libs/backends/jack/jack_audiobackend.cc
+++ b/libs/backends/jack/jack_audiobackend.cc
@@ -155,11 +155,11 @@ JACKAudioBackend::enumerate_devices () const
 }
 
 vector<float>
-JACKAudioBackend::available_sample_rates (const string& /*device*/) const
+JACKAudioBackend::available_sample_rates (const string& device) const
 {
 	vector<float> f;
 	
-	if (available()) {
+	if (device == _target_device && available()) {
 		f.push_back (sample_rate());
 		return f;
 	}
@@ -183,11 +183,11 @@ JACKAudioBackend::available_sample_rates (const string& /*device*/) const
 }
 
 vector<uint32_t>
-JACKAudioBackend::available_buffer_sizes (const string& /*device*/) const
+JACKAudioBackend::available_buffer_sizes (const string& device) const
 {
 	vector<uint32_t> s;
-	
-	if (available()) {
+		
+	if (device == _target_device && available()) {
 		s.push_back (buffer_size());
 		return s;
 	}