[DustyPorViva]

Okay, I think I found the issue out while messing around with some scripting.

Apparently, setmusicvolume left,right; is somehow stored with the exe(or registry, or something), and not reset when the client is exited. setmusicvolume 0,0; will remove all sound(not just music), and even if you close the editor and never open that level again the setting will persist.

An easy fix is to just make a level and put setmusicvolume 1,1; in an NPC and run the level.