I've tried switching to DX9, Uninstalling virtual audio cable, setting the default device in the app sound setting, and disabling all other audio devices. Trying to change any audio settings on my headphones with XIV open hard crashes the game, so I've been waiting the last 7 hours to get back into the game.

Sometimes combat is fine? Depends on the area and how many people are around i think. Did a trial and nothing went wrong, but it immediately got bad after.