--- gst-plugins-base-1.4.5/gst/playback/gststreamsynchronizer.c	2014-10-19 20:42:54.000000000 +0900
+++ gst-plugins-base-1.4.5/gst/playback/gststreamsynchronizer.c	2015-06-04 13:57:12.855095109 +0900
@@ -322,7 +322,10 @@
             }
           }
           position = MAX (0, position);
-          self->group_start_time = MAX (self->group_start_time, position);
+          self->group_start_time = position;
 
           GST_DEBUG_OBJECT (self, "New group start time: %" GST_TIME_FORMAT,
               GST_TIME_ARGS (self->group_start_time));