[Freeswitch-users] Method of checking if media is being played at a session

Hi All, I am dealing with a little problem... To play asynchronous audio in my Lua script I use the api function "uuid_broadcast {uuid} {fileName} aleg". This all works well and audio is being buffered if I call my function multiple times. When I want to abort all plays and flush the buffer I use "uuid_break {uuid} all". This all works excellent! My problem is I at certain points need to know if audio is being played (or awaits in the buffer) and need to pause execution untill all audio is beging played (or flushed). Is there a way of doing this in either Lua or apiFunctions? or a channel variable perhaps? I have looked and tryed but cannot seem to find a way doing this. Any hints (or solution ;-) appreciated! Regards, Michael Lutz