Ok. I chose the wrong way and it works
I had a function for embedding the object. This one been called by the "music on" button.
I made a function exactly the same function (with out any conditions etc. ) which embed an object which has hidden="true" and a src that doesn't exist.
This function been called with "music off".
This is maybe not the best way. But I just wanted to give user an extra option. The control keys for the music are actually on the player panel.