Using the new spacial sound pack DID NOT work for me either.
Maybe it gets slightly better if I set both my sound device and the game settings for spacial sound, and that's all. I still get stuttering sounds anywhere, specially in battles, and what's worse, during voice action on cutscenes.

There really doesn't seem to be anything we can do on our end that is a guaranteed fix. Some things work for some people, but nothing at all works for some (and I tried everything that was suggested, from dx9 to updating drivers, updating windows, terminating processes etc.).

We will have to hope on SE fixing this for us, and I just hope it happens soon, because I was so hyped for the new content, and now I can't know whether it will someday be playable on my computer…