diff --git a/libs/ardour/ardour/types.h b/libs/ardour/ardour/types.h
index 3f95d0c239..a43eb0125d 100644
--- a/libs/ardour/ardour/types.h
+++ b/libs/ardour/ardour/types.h
@@ -557,7 +557,8 @@ namespace ARDOUR {
 	struct RouteProcessorChange {
 		enum Type {
 			GeneralChange = 0x0,
-			MeterPointChange = 0x1
+			MeterPointChange = 0x1,
+			RealTimeChange = 0x2
 		};
 
 		RouteProcessorChange () : type (GeneralChange), meter_visibly_changed (true)
diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index a6a51c395e..5df1be71cb 100644
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -3407,7 +3407,7 @@ Route::apply_processor_changes_rt ()
 		}
 	}
 	if (changed) {
-		processors_changed (RouteProcessorChange ()); /* EMIT SIGNAL */
+		processors_changed (RouteProcessorChange (RouteProcessorChange::RealTimeChange)); /* EMIT SIGNAL */
 		set_processor_positions ();
 	}
 }
diff --git a/libs/ardour/session_transport.cc b/libs/ardour/session_transport.cc
index b392dabcbf..e953271ead 100644
--- a/libs/ardour/session_transport.cc
+++ b/libs/ardour/session_transport.cc
@@ -1826,6 +1826,12 @@ Session::route_processors_changed (RouteProcessorChange c)
 	}
 
 	if (c.type == RouteProcessorChange::MeterPointChange) {
+		set_dirty ();
+		return;
+	}
+
+	if (c.type == RouteProcessorChange::RealTimeChange) {
+		set_dirty ();
 		return;
 	}