Stopping double sound play

I have assigned actions to a button i have used, to play an mp3 file.

However, I don’t want the mp3 to play over and over if you keep pressing the button more than once.

How do you stop the recurring sound action?

i have assigned the stop button’s action window with:

on(release) {

and play button with:

on (release) {
kirupaSound = new Sound(this);
kirupaSound.start(0, 99);