GameMaker Audio

// DECLARE A GLOBAL SOMEWHERE, LIKE YOUR PERSISTENT GAME CONTROL OBJECT
global.SFX = -1;

// FORMAT EVERY SINGLE INSTANCE OF SFX LIKE: (
if(global.SFX != -1) audio_sound_gain(global.SFX, 0, 0);
global.SFX = audio_play_sound( put whatever you need to play here );
(Useful for excluding audio streams)

//IF YOU WANT AN IMMEDIATE END TO MULTIPLE AUDIO PROCESSES:
audio_stop_all ()