URGENT HELP NEEDED! Sound/Actionscript... it MUST be simple?

hi Guys

firstly, thanks for your help on previous topics.

i have a seven-scene movie with one audio track running the length of the movie. actionscript on scene 1 frame 1 is as follows:
var my_music:Sound = new Sound();
my_music.attachSound(“TomElliot_Final_1.mp3”);
my_music.start(0, 2);

this works fine. i would now like to add a sound on/off or ‘mute’ button (perhaps a check box component?) to allow the user to mute the audio without having to lower it manually on speakers or keyboard. i would imagine that some kind of

“if(checkbox)true;
my_music.setVolume(100)…”
or something similar. but then i could be COMPLETELY wrong as i don’t know what i’m talking about when it comes to actionmanscript. what i DON’T want is for the music to stop and re-start on this button, but to stream whether sound is on or off.

no volume slider or play/stop suggestions please.

otherwise your help, as always, is much appreciated.