To whatever extent the sound is intended to only give a general direction, I'd say quantize the angle and volume of the sound before it's sent such that cheaters also only get that same vague direction. Obviously don't send inaudible/essentially-inaudible sounds to the client at all.
They need to just make CPU's, GPU's, and memory modules with hardware level anti-cheat. Totally optional purchase, but grants you access to very-difficult-to-cheat-in servers.
That sort of already exists - I believe a small number of games demand that you have Secure Boot enabled, meaning you should only have a Microsoft-approved kernel and drivers running. And then the anticheat is itself probably kernel level, so can see anything in userspace
It may still be possible to get round this by using your own machine owner key or using PreLoader/shim [1] to sign a hacked Windows kernel
