Generator mp3 Sound Object

Hi.
I am trying to bring a sound clip into a Generator template with the inent of being able to control it's volume. I used the mp3 object, and attached it to a new Sound inside a new movie clip; e.g.;

myMasterLoop = new Sound(this);
myMasterLoop.attachSound("MasterLoop");

This worked in that I can control the volume,
however I cannot stop and start the clip.
Worse (and my main problem) is that it only plays through one time!
I have the object properties set to stream = false and cache = true.
(doesn't work with them set to true either).
Any idea what is going on here?
Thanx.