I just purchased a new Panasonic CT-27HL14. I've already tweaked it and it looks very nice, but there is a high pitch noise that occasionally shows up... Basically, it seems to come from motion. I am using it upstairs on a smallish TV stand (looking for a larger one soon). It sits comfortably, but the stand can move just a bit (but is stable) and the floor can shake a bit when moving around. If I shake the stand or step down hard on the floor, it will sometimes start the sound. I wedged a nice (TV size) piece of thick cardboard beneath it (so that the entire TV is resting on something). On my older Toshiba 20" flat screen set, tapping the floor or moving the set caused rather intense moire patterns to appear on the left and right side of the screen. With this set, it sometimes causes a high pitch sound. Not everybody even hears the sound, but it does bother me (though it isn't too bad with sound playing). If the sound begins, pressing down on the set or lifting it will always cause it to stop. Another note, I absolutely have a ground loop problem in this room. With both this set and my Toshiba, component video inputs will show very slight rolling bars at times. It isn't too bad and is only visible in gray colors (and isn't as severe on this new set). If the TV is set in the basement entertainment center (which is VERY stable), it will never make the noise as there is no way for it to move. What does this suggest? I'm trying to figure out exactly what the main culprit is. The slightly shakey area it stands upon, the ground loop problem, or an actual TV defect? I could swap it for another set, but I don't want to do that if I do not have to as the TV itself works beautifully.