diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 2ca1c28cb8..f4a4146480 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -5763,6 +5763,11 @@ Session::next_control_id () const
 	if (_monitor_out) {
 		subtract++;
 	}
+    
+    // the same about masterbus in Waves Tracks
+    if (Profile->get_trx() && _master_out) {
+		subtract++;
+	}
 
 	return nroutes() - subtract;
 }