diff --git a/libs/ardour/pannable.cc b/libs/ardour/pannable.cc
index d77c8a0e7f..abfb9d66c2 100644
--- a/libs/ardour/pannable.cc
+++ b/libs/ardour/pannable.cc
@@ -107,6 +107,12 @@ Pannable::set_panner (boost::shared_ptr<Panner> p)
 void
 Pannable::value_changed ()
 {
+	if (!has_state ()) {
+		// prevent the GUI from resetting panners
+		// e.g. when switching to aux-sends and back.
+		_has_state = true;
+	}
+
 	_session.set_dirty ();
 }