diff --git a/gtk2_ardour/engine_dialog.cc b/gtk2_ardour/engine_dialog.cc
index 9475d39ec2..3939fec8cb 100644
--- a/gtk2_ardour/engine_dialog.cc
+++ b/gtk2_ardour/engine_dialog.cc
@@ -1032,6 +1032,7 @@ EngineControl::backend_changed ()
 
 	if (!_have_control) {
 		// set settings from backend that we do have control over
+		set_buffersize_popdown_strings ();
 		set_active_text_if_present (buffer_size_combo, bufsize_as_string (backend->buffer_size()));
 	}