Low Volume on as3

Hy everyone,

I use this function to start the music in my project

function tocar() {
soundFactory.addEventListener(Event.COMPLETE, completeHandler);
soundFactory.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
soundFactory.addEventListener(ProgressEvent.PROGRESS, progressHandler);
song = soundFactory.play(); }

Now i wana low volume of the music. I thought it was something like song.volume = 90; but i was wrong :stuck_out_tongue:

Can u guys help me on this???