Controlling a timeline from nested buttons

programming flash
1

I have a straight forward flash document where the play head plays from start to finish. The client wants a way to stop and start the animation if time is needed to discuss what is happening on screen. Simple buttons can easily do this if those buttons are not nested.

Code:
stopBtn.addEventListener(MouseEvent.CLICK, onStopClick, false, 0, true);
playBtn.addEventListener(MouseEvent.CLICK, onPlayClick, false, 0, true);
stopBtn.buttonMode = true;
playBtn.buttonMode = true;
function onStopClick(evt:MouseEvent):void {
trace(“stop”);
root.stop();
}
function onPlayClick(evt:MouseEvent):void {
trace(“play”);
root.play();
}

However, if I make a mouse over pop up movie clip button and place those button inside it, they do not work. I can not find the piece of code that will link these nested buttons back to the main time line. Can anyone help?
Thanks.