Originally Posted by Lunateric
It could have been a variety of things, the cabinet that it was in was pretty solid and they had the transmitter beneath the other electronics in the cabinet. Being only a couple feet from the TV I can't imagine that this was an expected condition. I did notice that when the salesman opened the cabinet and reached in to operate the DVD player the distortion was more pronounced, so there had to be something else at play.
There is definitely some line-of-sight considerations with the wireless transmitter. It's also implied via some of the diagrams in the owners manual. When my wife works out in front of the TV, there is an occasional minor glitch. Otherwise it's rock-solid.
If you are concerned about this you could of course simply bypass the wireless and plug straight in. The TV is still a raging bargain for it's picture quality even ignoring the wireless feature. But the glitches I've seen are so rare and minor that to me it's not worth the 2 minutes of effort to run the HDMI cable.
If you are wound extremely tight about this stuff, you should also know that when turning the TV on, there is delay of several seconds while the TV establishes the connection with the wireless box.