ActionScript 2.0 :: Code To Stop Songs From Overlapping?

I'm working on a music player in Flash actionscript 2.0, because I can't get any codes that I've found for 3.0 to work. So surely it's obvious that I am not a coder. I've made each of the three songs have it's own play button, with its name on it. The buttons play like they should, however, if a song is playing and you choose to play another instead, the second song will play over the first. So the first song is not stopping. I have a stop button that will terminate all of the sounds. But since the player will be publicly displayed, I want to make sure that people aren't inconvenienced by having to use the stop button every time that they want to change songs while one is in play. I'm having the same overlapping problem if a song button is double clicked or mistakenly pressed while it's already playing.Here is the code for one of the buttons. Can I add the stop function to it? If so, how? Or do I need a completely different code to achieve this?

Code:
apartofme_button.onRelease = function(){
mySong = new Sound();

[code]....