diff --git a/gtk2_ardour/ardour_ui.cc b/gtk2_ardour/ardour_ui.cc
index 0314e6445e..70daa60cc7 100644
--- a/gtk2_ardour/ardour_ui.cc
+++ b/gtk2_ardour/ardour_ui.cc
@@ -3125,6 +3125,7 @@ ARDOUR_UI::load_session (const std::string& path, const std::string& snap_name,
 	session_loaded = true;
     
     tracks_control_panel->refresh_session_settings_info();
+    _session->config.ParameterChanged.connect_same_thread (connection_with_session_config, boost::bind (&ARDOUR_UI::on_parameter_changed, this, _1));
 
 	goto_editor_window ();
 
@@ -3174,6 +3175,8 @@ ARDOUR_UI::build_session (const std::string& path, const std::string& snap_name,
 		return -1;
 	}
     
+    _session->config.ParameterChanged.connect_same_thread (connection_with_session_config, boost::bind (&ARDOUR_UI::on_parameter_changed, this, _1));
+    
     new_session->config.set_native_file_header_format(this->_header_format);
     new_session->config.set_native_file_data_format  (this->_sample_format);
     new_session->config.set_timecode_format(this->_timecode_format);
@@ -3198,14 +3201,22 @@ ARDOUR_UI::build_session (const std::string& path, const std::string& snap_name,
 	}
 
 	set_session (new_session);
-
-	session_loaded = true;
-
+    session_loaded = true;
+    
 	new_session->save_state(new_session->name());
 
 	return 0;
 }
 
+void
+ARDOUR_UI::on_parameter_changed(std::string param)
+{
+    if (param == "native-file-data-format" || param == "native-file-header-format")
+        update_format();
+    if ( param == "timecode-format")
+        update_timecode_format();
+}
+
 void
 ARDOUR_UI::launch_chat ()
 {
diff --git a/gtk2_ardour/ardour_ui.h b/gtk2_ardour/ardour_ui.h
index 5166896525..01baa45d7a 100644
--- a/gtk2_ardour/ardour_ui.h
+++ b/gtk2_ardour/ardour_ui.h
@@ -307,8 +307,6 @@ class ARDOUR_UI : public Gtkmm2ext::UI, public ARDOUR::SessionHandlePtr
     void set_sample_format(ARDOUR::SampleFormat sf) {_sample_format = sf;}
     void set_header_format(ARDOUR::HeaderFormat hf) {_header_format = hf;}
     void set_timecode_format(Timecode::TimecodeFormat tc) {_timecode_format = tc;}
-    void update_format ();
-    void update_timecode_format ();
     
   protected:
 	friend class PublicEditor;
@@ -559,6 +557,9 @@ class ARDOUR_UI : public Gtkmm2ext::UI, public ARDOUR::SessionHandlePtr
 	void update_sample_rate (ARDOUR::framecnt_t);
 
 	Gtk::Label    format_label;
+    void update_format ();
+
+    void update_timecode_format ();
 	
 	gint every_second ();
 	gint every_point_one_seconds ();
@@ -783,6 +784,8 @@ class ARDOUR_UI : public Gtkmm2ext::UI, public ARDOUR::SessionHandlePtr
     ARDOUR::HeaderFormat _header_format;
     Timecode::TimecodeFormat _timecode_format;
     
+    void on_parameter_changed(std::string);
+    PBD::ScopedConnection connection_with_session_config;
 };
 
 #endif /* __ardour_gui_h__ */
diff --git a/gtk2_ardour/ardour_ui_dialogs.cc b/gtk2_ardour/ardour_ui_dialogs.cc
index 35dbe3cfc9..7b9fc16e86 100644
--- a/gtk2_ardour/ardour_ui_dialogs.cc
+++ b/gtk2_ardour/ardour_ui_dialogs.cc
@@ -189,6 +189,7 @@ ARDOUR_UI::set_session (Session *s)
 	point_zero_something_second_connection = Glib::signal_timeout().connect (sigc::mem_fun(*this, &ARDOUR_UI::every_point_zero_something_seconds), 40);
 
 	update_format ();
+    update_timecode_format();
 
 	if (meter_box.get_parent()) {
 		transport_tearoff_hbox.remove (meter_box);
@@ -279,6 +280,7 @@ ARDOUR_UI::unload_session (bool hide_stuff)
 	second_connection.disconnect ();
 	point_one_second_connection.disconnect ();
 	point_zero_something_second_connection.disconnect();
+    connection_with_session_config.disconnect();
 
 	if (editor_meter) {
 		meter_box.remove(*editor_meter);
diff --git a/gtk2_ardour/tracks_control_panel.logic.cc b/gtk2_ardour/tracks_control_panel.logic.cc
index ec6f484728..c5c70a694e 100644
--- a/gtk2_ardour/tracks_control_panel.logic.cc
+++ b/gtk2_ardour/tracks_control_panel.logic.cc
@@ -1265,9 +1265,6 @@ void TracksControlPanel::update_session_config ()
             session->config.set_native_file_header_format( string_to_HeaderFormat(_file_type_combo.get_active_text() ) );
             session->config.set_native_file_data_format  ( string_to_SampleFormat(_bit_depth_combo.get_active_text() ) );
             session->config.set_timecode_format(           string_to_TimecodeFormat(_frame_rate_combo.get_active_text() ) );
-            
-            ardour_ui->update_format();
-            ardour_ui->update_timecode_format();
         }
     }
 }
diff --git a/libs/backends/wavesaudio/wscript b/libs/backends/wavesaudio/wscript
index 3f3a7080b7..2b3684b0fd 100644
--- a/libs/backends/wavesaudio/wscript
+++ b/libs/backends/wavesaudio/wscript
@@ -32,8 +32,11 @@ def build(bld):
 	obj = bld(features = 'c cxx cxxshlib')
     
     if sys.platform == 'darwin':
-        obj.framework = 'CoreMidi'
-  
+        if bld.env['build_target'] not in [ 'lion' ]:
+            obj.framework = 'CoreMidi'
+        else:
+            obj.framework = 'CoreMIDI'
+
     obj.source = [
             'waves_audiobackend.cc',
             'waves_audiobackend.latency.cc',