Ive got a similar problem that unfortunately has not been fixed by changing the above settings. I started out having the buzzing dialogue like most people and the change to 44100hz did indeed fix that, however the problem seems to be larger than that now. All spell sound effects and a majority of background noises are filled with static, casting something like Healing creates such a huge blast of static I almost can't even play the game. Ive gone through most of the Hz settings and nothing fixed it, my sound card drivers are up to date and ive never had any problem like this in any game or anything ever before.