diff --git a/gtk2_ardour/add_route_dialog.cc b/gtk2_ardour/add_route_dialog.cc
index 07d5662a50..a3fc0ba730 100644
--- a/gtk2_ardour/add_route_dialog.cc
+++ b/gtk2_ardour/add_route_dialog.cc
@@ -516,13 +516,7 @@ AddRouteDialog::build_instrument_list ()
 
 		if (manager.get_status (*i) == PluginManager::Hidden) continue;
 
-		string category = (*i)->category;
-		
-		/* XXX more finesse is possible here. VST plugins have a
-		   a specific "instrument" flag, for example.
-		*/
-
-		if ((*i)->n_inputs.n_midi() != 0 && (*i)->n_outputs.n_audio() > 0) {
+		if ((*i)->is_instrument()) {
 			row = *(instrument_list->append());
 			row[instrument_list_columns.name] = (*i)->name;
 			row[instrument_list_columns.info_ptr] = *i;
diff --git a/libs/ardour/ardour/plugin.h b/libs/ardour/ardour/plugin.h
index 0c2bcbdd93..ec185b3a31 100644
--- a/libs/ardour/ardour/plugin.h
+++ b/libs/ardour/ardour/plugin.h
@@ -65,6 +65,7 @@ class PluginInfo {
 	std::string unique_id;
 
 	virtual PluginPtr load (Session& session) = 0;
+	virtual bool is_instrument() const; 
 
   protected:
 	friend class PluginManager;
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index 69155f54b3..abf4999e7f 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -316,13 +316,13 @@ AudioEngine::_xrun_callback (void *arg)
 void
 AudioEngine::_session_callback (jack_session_event_t *event, void *arg)
 {
-	printf( "helo.... " );
 	AudioEngine* ae = static_cast<AudioEngine*> (arg);
 	if (ae->connected()) {
 		ae->JackSessionEvent ( event ); /* EMIT SIGNAL */
 	}
 }
 #endif
+
 int
 AudioEngine::_graph_order_callback (void *arg)
 {
diff --git a/libs/ardour/plugin.cc b/libs/ardour/plugin.cc
index bac014df38..cbcf9f7f7c 100644
--- a/libs/ardour/plugin.cc
+++ b/libs/ardour/plugin.cc
@@ -62,6 +62,12 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
+bool
+PluginInfo::is_instrument () const
+{
+	return (n_inputs.n_midi() != 0) && (n_outputs.n_audio() > 0);
+}
+
 Plugin::Plugin (AudioEngine& e, Session& s)
 	: _engine (e)
 	, _session (s)