Please head over to [Main Thread] Frame Rate Hitching / Stuttering on PC 4090 - #252 by ShadWalker-1719
I know that’s a long thread at this point, but there are a ton of ideas that the community has come up with in there. Seems as though about half of the people who had stuttering issues got them resolved by following that thread.
For me personally, it was telling Windows that my home network was ‘public’ (untrusted network), which is more restrictive than setting it to ‘private’ (trusted network). Doing that made it so that the game stopped constantly polling my audio devices, which I believed to be a cause of the hitching.
Good luck everyone! And it’s a shame that the Blizz technical community managers have been mostly inactive 