I did an AS3 mute button and in light of your project I think you could do one that that addressed multiple sound objects with AND statements inside a button OnPress function using volume control.
A true mute button is really a volume control toggle that allows the sounds to continue playing..
AS1 would be different but the idea is the same: This is just pseudocode but for multiple sounds it might look something like:
Actionscript Code:
function onPress {
if snd1.volume > 0 AND snd2.volume > 0 AND snd3.volume > 0 then
snd1.volume = 0 AND snd2.volume = 0 AND snd3.volume = 0
}else{
snd1.volume = 1 AND snd2.volume = 1 AND snd3.volume = 1
}
someone good at AS1 would need to verify though. Maybe it needs to use getVolume() and setVolume()?