Author: Me (I mean, it really wasn't that hard.)
Difficulty: Really Easy
What does it do?
It enables / disables environmental ambient sound by pressing Shift + 0. (People claim that it gives you better FPS.)
In my case, it gives me an extra 2 - 6 FPS depending on how much ambient sound there is.
https://community.bistudio.com/wiki/enableEnvironment
I've made it so that it only disables / enables ambient sound.
Here it is:
Step 1: Go to core\configuration.sqf - Add 'life_environment = 0;'
Do it like this:
Step 2: Go to core\functions