Comment 2 for bug 1183146

StacktraceTop:
 g_type_check_instance_is_a (type_instance=type_instance@entry=0x295ad50, iface_type=iface_type@entry=35217760) at /build/buildd/glib2.0-2.36.0/./gobject/gtype.c:3999
 brasero_audio_disc_session_changed (session=0x7f49ac006d10, self=0x1ea1cc0) at brasero-audio-disc.c:906
 g_closure_invoke (closure=0x229bc90, return_value=0x0, n_param_values=1, param_values=0x7fffcd860830, invocation_hint=0x7fffcd8607d0) at /build/buildd/glib2.0-2.36.0/./gobject/gclosure.c:777
 signal_emit_unlocked_R (node=node@entry=0x2323000, detail=detail@entry=0, instance=instance@entry=0x7f49ac006d10, emission_return=emission_return@entry=0x0, instance_and_params=instance_and_params@entry=0x7fffcd860830) at /build/buildd/glib2.0-2.36.0/./gobject/gsignal.c:3584
 g_signal_emit_valist (instance=0x7f49ac006d10, signal_id=<optimized out>, detail=0, var_args=var_args@entry=0x7fffcd860a78) at /build/buildd/glib2.0-2.36.0/./gobject/gsignal.c:3328