diff --git a/gtk2_ardour/mixer_strip.cc b/gtk2_ardour/mixer_strip.cc
index b11751d957..3fb377bf9e 100644
--- a/gtk2_ardour/mixer_strip.cc
+++ b/gtk2_ardour/mixer_strip.cc
@@ -510,6 +510,8 @@ MixerStrip::set_route (boost::shared_ptr<Route> rt)
 	route_ops_menu = 0;
 
 	_route->meter_change.connect (route_connections, invalidator (*this), bind (&MixerStrip::meter_changed, this), gui_context());
+	_route->input()->changed.connect (*this, invalidator (*this), boost::bind (&MixerStrip::update_output_display, this), gui_context());
+	_route->output()->changed.connect (*this, invalidator (*this), boost::bind (&MixerStrip::update_output_display, this), gui_context());
 	_route->route_group_changed.connect (route_connections, invalidator (*this), boost::bind (&MixerStrip::route_group_changed, this), gui_context());
 
 	if (_route->panner_shell()) {