When dealing with complex audio situations it can be useful to
define where in the audio environment the listener should be
situated. When working with the simple audio functions, it is not
normally necessary for the listener to be changed in any way,
however when using emitters to generate realistic audio within the
3D audio space, it is important that the listener be changed and
moved correctly, or else the sound will be in the wrong
position for the person playing your game.
GameMaker: Studio provides the following listener
functions:
Certain target platforms can permit more than one listener, with each one corresponding to a different output device, ie: your target platform could permit two listeners, one for the headphones and one for the monitor. Therefore GameMaker: Studio provides you with a number of extra functions with which you can find the available listeners as well as set them for sounds being played: