Sound-refference slettes ikke

Hej eksperter!

Hvorfor slettes objektet SOUND ikke i følgende kode?:

var TEMP:Sound = new Sound(SOUNDS.ATTACH("SOUND_missile_launch"));
EMP.setVolume(TEMP.getVolume()/2);
delete TEMP;
trace(TEMP);

Output bliver:
[object Object]

Bemærk klassen SOUNDS:

class SOUNDS {
   
    private static var MAX:Number = new Number(50);
    private static var DEPTH:Number = new Number(0);
   
    public static function ATTACH(_SOUND:String):Sound {
        if (_root.SOUND) {
            if (DEPTH >= MAX-1) {
                DEPTH = 0;
            } else {
                DEPTH++;
            }
            _root.AUDIO["SOUND"+DEPTH] = new Sound();
            _root.AUDIO["SOUND"+DEPTH].attachSound(_SOUND);
            _root.AUDIO["SOUND"+DEPTH].start();
            return _root.SOUNDS["SOUND"+DEPTH];
        }
    }
   
}