AS3.0 静音和停止所有声音

import flash.media.SoundTransform;
import flash.media.SoundMixer;
/////////静音/////////////
soundoff.addEventListener(MouseEvent.CLICK,offoff);
function offoff(overas:MouseEvent) :void
{
   var transform:SoundTransform=SoundMixer.soundTransform;
   transform.volume=0;
    // transform.volume=1;
  SoundMixer.soundTransform=transform;
   gotoAndStop(2);
}
/////////停止所有声音/////////////
soundoff.addEventListener(MouseEvent.CLICK,offoff);
function offoff(overas:MouseEvent) :void
{
   SoundMixer.stopAll();
   gotoAndStop(2);
}