Music overlapping with "kirupasound" actionscript

Hi guys

Ive been developing a flash file (actionscript 2.0 in Flash CS4) to import into a website Im designing. So far I am using this action:

 
on (release) {
kirupaSound = new Sound(this);
kirupaSound.attachSound("erikasong");
kirupaSound.start(0, 0);
}

in my buttons in order to play individual sound files. The sound files are playing great but they overlap one another. How can I can either create a stop button or modify the code so that when the user clicks on the next sound button, the old music stops and the new begins?

Sorry - this is my first week of flash - I normally deal with just graphical design.

Tom.