Well you havent given us very much to go on here, there is no indication of how you have set your code up and so its very hard to say how to fix it.
All I can do is give you some general advice. If you are playing all of the sounds through the same audiostream you could check if it is playing and only play if it isnt playing
if not $yourAudiostramplayer.is_playing():
your code here
this will only work if they are all using the same audioplayer though, if not they wont detect it.