diff --git a/gtk2_ardour/ardour_ui_engine.cc b/gtk2_ardour/ardour_ui_engine.cc
index 2d63542109..9b2e46373c 100644
--- a/gtk2_ardour/ardour_ui_engine.cc
+++ b/gtk2_ardour/ardour_ui_engine.cc
@@ -130,7 +130,7 @@ ARDOUR_UI::halt_on_xrun_message ()
 void
 ARDOUR_UI::xrun_handler (samplepos_t where)
 {
-	if (!_session) {
+	if (!_session || where < 0) {
 		return;
 	}