As? change soundservice properties according to player zone

basically I want that when the player is in a zone some soundservice properties are changed (locally) I want to do it in the most optimized way possible because it is a FPS game and I need that it does not affect in ANY way the FPS, personally I think that the touched event must be managed well so I want you to tell me how to make it more optimized … if you think that the touched event is not an option to optimize then tell me a technique with runservice, but try that it is not with lightning.
I don’t want a script I just want pointers and tips