rem: return xine_open_audio_driver (gtx->priv->xine,
add: if (strcmp (audio_driver_id, "auto") == 0) return xine_open_audio_driver (gtx->priv->xine, NULL, NULL);   ao_driver =  xine_open_audio_driver (gtx->priv->xine,
context: load_audio_out_driver (GtkXine *gtx, const char *audio_driver_id){	if (strcmp (audio_driver_id, "null") == 0)		return NULL;	return xine_open_audio_driver (gtx->priv->xine,			audio_driver_id, NULL);}