Hello everyone, I am trying to solve the gapless issue programming the event triggered for that signal. I am handling video files (.avi) The code is very straightforward andn simple, nonetheless it doesn't work. It plays the first and for the second one it throws the following message: (playbin:4324): GLib-GObject-CRITICAL **: g_object_set: assertion `G_IS_OBJECT (object)' failed Any suggestion? thansks Rossana Here is the code: void about_to_finish_cb (GstElement * element, gpointer * uri) { // uri has the name of the next avi file gchar* uri2 = (gchar*)uri; g_object_set (G_OBJECT (element), "uri",uri2, NULL); g_object_set (G_OBJECT (element), "suburi","file:///home/rossana/video3.srt", NULL); } gint main (gint argc, gchar *argv[]) { GMainLoop *loop = 0; GstElement *play = 0; GstBus *bus = 0; /* set up */ gst_init (&argc, &argv); loop = g_main_loop_new (NULL, FALSE); play = gst_element_factory_make ("playbin2", "play"); g_object_set (G_OBJECT (play), "uri","file:///home/rossana/video1.avi", NULL); bus = gst_pipeline_get_bus (GST_PIPELINE (play)); gst_bus_add_watch (bus, bus_call, loop); gst_object_unref (bus); char uri_next[] = "file:///home/rossana/video3.avi"; g_signal_connect (play, "about-to-finish", G_CALLBACK (about_to_finish_cb),uri_next); gst_element_set_state (play, GST_STATE_PLAYING); /* now run */ g_main_loop_run (loop); /* also clean up */ gst_element_set_state (play, GST_STATE_NULL); gst_object_unref (GST_OBJECT (play)); return 0; }