diff --git a/gtk2_ardour/audio_clock.cc b/gtk2_ardour/audio_clock.cc
index 6680e95b15..b24d22f1b9 100644
--- a/gtk2_ardour/audio_clock.cc
+++ b/gtk2_ardour/audio_clock.cc
@@ -620,6 +620,9 @@ AudioClock::end_edit (bool modify)
 			break;
 
 		case Frames:
+			if (edit_string.length() < 1) {
+				edit_string = pre_edit_string;
+			}
 			break;
 		}