Second day with the new 65GT50 and sadly I am missing my 58" pz850u (sold it to a buddy). The GT50 is more modern looking, has deeper blacks, and better motion resolution as expected... but I am considering returning it for several reasons. First, I have a real "buzzer". If I have volume set lower than 25, I can clearly hear a buzz from 10 feet away when there is a bright image on the screen... and that's with panel brightness set to low. In fact, the buzz can overwhelm the TV volume at a 10 or lower setting. I never heard anything other than a little fan noise from my 850u. Second, the sound quality is really poor (tinny) no matter what audio settings I try. I guess it's a by-product of these ever thinner panels. Lastly, it really bugs me that the image for 16:9 content (and TV set to "Full" wide) comes up almost 1/4" short of the bezel on all sides. Is this normal ? I also noticed that the image shifts intermittently to the point where the gap on one side is even wider. (I'm guessing this is the pixel orbiter). The image on my 850u filled the screen from bezel edge to bezel edge and I never noticed any pixel orbiting. I think I can tolerate the last two issues but not the buzzing.
I've read a little bit about the buzzing issue and it almost seems that some level of buzzing is now considered "normal" and most members with this problem seem to be working on their own fixes. Has anyone been able to get some kind of satisfactory resolution from Panasonic service ?