setInterval help!

Hi everybody,

I am running into a serious problem here. I have few sound files and I need to play then in an order and every time after the sound played a button is active then the user can click on the button to play next sound…ect. But at some point my setInterval keep calling the stop sound function even though myTimer is delete, Will anybody has an idea how can I deal with it? I checked the actionscript dictionary and I found that the delete action is for Flash 5. Does it mean I can use it in Flash 7 or 8 and actionscript2?

Here is the code my created:
//-----------play sound---------//
function soundPlay(ID:Number){
var instrSound:Sound = new Sound(this);
var soundName:String = “SCP” + ID + “.wav”;
soundID = ID;
var curSoundDur:Number = instrSound.duration;
myTimer = setInterval(stopSound,curSoundDur);

//-------------stop sound-------------//
function stopSound(){
if(soundID == 1){
testingButton._visible = true;
if(myTimer != null){
delete myTimer;