diff --git a/gtk2_ardour/export_format_dialog.cc b/gtk2_ardour/export_format_dialog.cc
index 195d7c8fe4..5c1ec5d1dc 100644
--- a/gtk2_ardour/export_format_dialog.cc
+++ b/gtk2_ardour/export_format_dialog.cc
@@ -993,8 +993,7 @@ ExportFormatDialog::update_silence_end_selection ()
 void
 ExportFormatDialog::update_clock (AudioClock& clock, ARDOUR::AnyTime const& time)
 {
-	// TODO position
-	clock.set (timepos_t (_session->convert_to_samples (time)), true);
+	clock.set_duration (timecnt_t (_session->convert_to_samples (time)));
 
 	AudioClock::Mode mode (AudioClock::Timecode);