diff --git a/subprojects/gst-plugins-bad/gst/mpegtsdemux/tsdemux.c b/subprojects/gst-plugins-bad/gst/mpegtsdemux/tsdemux.c
index b4655a35da..fb19acf4eb 100644
--- a/subprojects/gst-plugins-bad/gst/mpegtsdemux/tsdemux.c
+++ b/subprojects/gst-plugins-bad/gst/mpegtsdemux/tsdemux.c
@@ -976,6 +976,7 @@ gst_ts_demux_do_seek (MpegTSBase * base, GstEvent * event)
     if (G_UNLIKELY (start_offset == -1)) {
       GST_WARNING_OBJECT (demux,
           "Couldn't convert start position to an offset");
+      g_mutex_unlock (&demux->lock);
       goto done;
     }