Electronically, this is the occasional formation of an electrical arc--a momentary stream of electricity directly through the air--from one point to another on the video output module (the square board and apparatus connected to the small end of the picture tube). If you happen to be peering into the set when the electrical arc occurs, you will see it quite vividly. It is essentially a momentary short-circuiting, but through the air rather than across a wire or other metal. It is somewhat similar to a spark of static electricity or a miniature bolt of lightning!
When I first got the C32V37, the problem was severe enough that this occasional electric arc would cause the momentary collapse of the screen's picture, rather like a momentary power outage. (Note that my C32V37 is on an Uninterruptible Power Supply with Automatic Voltage Regulation, so the problem is not actually related to any external power glitching.) In addition, the arc would make a very loud zapping sound.
After the repairman reduced the gross brightness (amperage?) of the set, the screen's picture no longer visibly reacts to the electrical arc-ing. The arc's sound is also less jarring, more like a snap than a zap. Nevertheless, everyone agrees that an HDTV set should not be doing this. As I mentioned earlier, the repairman has ordered a new video output module, but I suspect that the part is backordered, because over a week has passed without a call from him.
A couple other notes:
- The arc-ing seems to be more frequent on warmer days (e.g., over 70 degrees).
- Because the gross brightness has been lowered, I now have to set the video brightness at 80 to 95 in order to attain a correct picture as measured by the THX Optimizer.