My wife and I just bought a C32V37 last week (in no small part because of its great rep on this site), and Comcast set us up with a Motorola 6200 yesterday. Basically, we love the set, but last night we noticed the white bar during the Sopranos. To my eye, the problem seems less pronounced today, so I don't know if it is a specific issue with HBOHD. I haven't seen the problem on another channel yet.
I've emailed Zenith (wanted to try that before the expected hell of 1-800 numbers), and am waiting to hear from them.
Reading the relevant thread on the similar problem with the Sonys, the diagnosis there was:
"Its the horizontal deflection circuit getting coupled into the video
signal. In the 1080i case they typically differ in frequency by about 1
cycle per second - hence the moving bar across the screen. For other types
of inputs (480i, 480p, 720p) the frequency difference between the
horizontal scan and the video sync is much larger (about 2.7kHz for 480i
signals). In that case, the coupling is still there but its effect is
And many people were able to fix it by adjusting a setting in the service menu. Obviously, I don't know if it's the same issue with the Zenith.
Hopefully, we can resolve this soon, as it is otherwise a really great TV.
Trying to break bad hobbits ...