diff --git a/gtk2_ardour/midi_region_view.cc b/gtk2_ardour/midi_region_view.cc
index b9af0a81a2..d020a13d88 100644
--- a/gtk2_ardour/midi_region_view.cc
+++ b/gtk2_ardour/midi_region_view.cc
@@ -764,8 +764,8 @@ MidiRegionView::add_note(const boost::shared_ptr<Note> note)
 		ev_rect->property_y2() = y1 + floor(midi_stream_view()->note_height());
 
 		if (note->duration() == 0) {
-			cerr << "MidiModel: WARNING: Discovered note with duration 0 and pitch" << note->note() 
-			     << " at time " << note->time() << endl;
+			cerr << "MidiModel: WARNING: Discovered note with duration 0 and pitch"
+				<< (int)note->note() << " at time " << note->time() << endl;
 			if (_active_notes) {
 				assert(note->note() < 128);
 				_active_notes[note->note()] = ev_rect;
diff --git a/libs/ardour/midi_model.cc b/libs/ardour/midi_model.cc
index b4e2c54d3c..8819423694 100644
--- a/libs/ardour/midi_model.cc
+++ b/libs/ardour/midi_model.cc
@@ -101,8 +101,12 @@ MidiModel::const_iterator::const_iterator(const MidiModel& model, double t)
 		}
 
 		assert(x >= 0);
-		assert(y >= i->first.min());
-		assert(y <= i->first.max());
+
+		if (y >= i->first.min() || y <= i->first.max()) {
+			cerr << "ERROR: Event value '" << y << "' out of range ["
+				<< i->first.min() << "," << i->first.max() << "], ignored" << endl;
+			continue;
+		}
 
 		const MidiControlIterator new_iter(i->second->list(), x, y);