The first sign of trouble was during the cutscene where Thordan speaks in private to one of his knights. All I hear is the echo of the voices in the hall but not the voices themselves so it's really hard to hear what they're saying. In boss battles like Ravana the voices also sounded very faint and distant. I finally realized that I was missing out on voiced cutscenes when I looked up YouTube playthroughs of Heavensward and saw the narration when you enter a new region is voiced! I have no idea what's going on! I recently installed a new audio card since the on board audio got busted somehow, so maybe it has something to do with that?