I had an extremely obnoxious kiai sound from when I used to play the game. I tried to deactivate it mutliple times, but I still here it when I play multiplayer. I sold the item, and yet I'm still hearing it. I'm not sure if anyone else can hear it, but I don't know how to fix it.

Turn game volume down.

You're so smart, enclave.
ZionNinja, go to your custom folder (if you use steam version, it'll be ?steam\steamapps\common\Toribash\custom), find there folder with your name and delete it. next time you will go multiplayer it will be downloaded automatically with your current set

I'll try that, thanks Nikorn