On Tue, 2015-12-29 at 09:03 +0530, arun at accosted.net wrote: > +/** Set the callback function that is called whenever the volume of the stream > + * changes. \since 9.0 */ > +void pa_stream_set_volume_changed_callback(pa_stream *p, pa_stream_notify_cb_t cb, void *userdata); It should be documented that this only works starting from protocol version 31. -- Tanu