First of all, welcome to the forum.
I'm not sure what's happening here exactly, but the symptoms you describe definitely point to operation that I wouldn't consider normal operation. The best recommendation I can make is to have a service call - often times they can come to you, and you may be able to arrange a weekend or a time that might work for you. I understand you probably have a busy schedule, however, I do think getting your unit serviced would be the best solution.
Keep me posted.
I posted this in another thread, then I got to thinking maybe I shouldn't piggyback onto to another for a different TV.
Was having an intermittent problem with no picture when turning on the TV. Updated the firmware to latest thinking it might help. Now, I turn on the TV and I sometimes get a fuzzy bright green screen and very loud static. (This did not happen immediately after the firmware update.) Remote seems somewhat unresponsive. I'll hit the power switch and nothing will happen immediately. Then it might either go off or "fully" come on with a picture. I have tried turning the TV on before and after the cable box was turned on. Since I do not get the "no signal" message when the cable box is off I think I have effectively isolated the problem to the TV. I work all week, so do not have the time to be waiting for a repairman or to be taking it somewhere. Plus, it is my only TV. Anyone else getting that green screen?