Comment 34 for bug 298494

It worked for me ! In fact it was easier than that ... I just uninstalled (using synaptic) the gstreamer0.10-plugins-ugly package, which used the 0.10.9-1ubuntu0.1 version, and installed the gstreamer0.10-plugins-ugly-multiverse, which uses a variant 0.10.7-2 version that doesn't exhibit the problem. You need to have the multiverse repository enabled in synaptic/adept.
Many thanks ! I think this issue is solved !