I have the same set and the same problem. I contacted the seller and they said that it was normal for the set to make noise as it warms up and cools. I had to explain that it sounded like a transformer on a utility pole getting ready to explode. I contacted my cable company and they said it was the tv not the cable.(shocker)
The seller suggusted that I try to get a newer HD cable box. He stated that they are not the best quality and it may help. I have not done this yet but will let you know if any thing gets better.
I have had a LN46A550 and an Onkyo TX-SR606 receiver for a few months, with a DVD player and AT&T Uverse cable box connected to the receiver. Everything was fine initially, but now when I turn on the receiver and TV, there is a loud burst of popping/cracking sound produced from the TV. This sound may last 30 seconds or sometimes longer, gradually tapering off. The sound only comes from one side, the left side. I have already taken the receiver in to be checked, and the report came back that there were no problems with the receiver. More specifics:
? Even after the initial burst of sound tapers off, there is still a persistent soft popping and occasional loud pop produced from the TV.
? All connections are HDMI.
? No popping sound from audio speakers. Only from the TV.
? These popping sounds are produced even though the TV speakers are muted through the TV?s controls.
? When I connect the cable box directly to TV, there is no popping sound from the TV at all. It is only when cable box input to the TV is through the receiver that there is this horrible noise upon start up.
? When DVD is selected on receiver and DVD player is connected to receiver, there is no problem. The TV makes no popping sounds at all. It's only when CBL/SAT is selected that the problem occurs.
? I used different HDMI cables, the problem persists.
? TV has three HDMI inputs. Doesn?t matter which one used, same popping sounds happens.
? I disconnected all other sources, the problem persists.
? I disconnected all audio speakers (center, front, surround back, surround, subwoofer), the problem persists.
? I plugged the power cords from TV, receiver, other sources all into separate outlets, the problem persists.
I've probably spent 8 hours trying to figure this out. I suppose my next step would be to take the TV in to be checked, but before I go through all that effort... anybody got any ideas?