diff --git a/gtk2_ardour/route_properties_box.cc b/gtk2_ardour/route_properties_box.cc
index 46ecd63c7b..d999f4f032 100644
--- a/gtk2_ardour/route_properties_box.cc
+++ b/gtk2_ardour/route_properties_box.cc
@@ -72,6 +72,9 @@ RoutePropertiesBox::session_going_away ()
 void
 RoutePropertiesBox::set_route (std::shared_ptr<Route> r)
 {
+	if (r == _route) {
+		return;
+	}
 	assert (r);
 	_route = r;
 	_route_connections.drop_connections ();