A quick sshot of what I'm showing on my end. It let's me select the eq such as acoustic. However the eq graph never changes and when I adjust it manually nothing happens audibly.
The EQ Graph doesn't change with me either when I select the preset Rock, but I do notice the difference in sound. What headset are you using? I have given up on the cords and went Bluetooth. So to test headset settings I would have to connect it to my 5.1 computer speakers.
Posible work around for Stock Wifi tether. If you are having issues with it turning off after applying additional themes and what nots. Go into the Settings/Apps/All and open "entitlement" and force stop then reboot. Wifi tether should work after booting back up.