90312 - Thanks, I thought I saw that it had to be approved before it would appear, but the screen went away too quick for me to read it. Good to know.
CBR929 - Thank you, I saw the forum, but it appears the original buzzing issue has been fixed, but only in the result of another issue where the center sound comes out of the front left speaker.
I did try the fix from Wilson.Wang, but this creates an M4V file rather than an MP4 and I would like to try and keep my movies in an MP4 format.
As an alternative, it appears I can use the Dolby Prologic II audio format with the Apple TV profile until everything has been completely resolved.