===================================================================
RCS file: /cvs/gstreamer/gst-plugins-base/ext/ogg/gstoggmux.c,v
retrieving revision 1.92
diff -u -r1.92 gstoggmux.c
--- ext/ogg/gstoggmux.c 9 Aug 2007 11:37:28 -0000       1.92
+++ ext/ogg/gstoggmux.c 5 Oct 2007 13:32:23 -0000
@@ -533,8 +533,10 @@
   }
 
   caps = gst_pad_get_negotiated_caps (mux->srcpad);
-  gst_buffer_set_caps (buffer, caps);
-  gst_caps_unref (caps);
+  if (caps) {
+    gst_buffer_set_caps (buffer, caps);
+    gst_caps_unref (caps);
+  }
 
   return gst_pad_push (mux->srcpad, buffer);
 }