I just bought a LN52A650-B and am having the same problem. This feature is so nauseating; I can't stand it. I keep shutting it off, and it keeps coming back on. I don't even have to change channels. Please let me know how I can turn it off permanently.
I have had some problems with the auto motion plus. It gives the soap opera effect when I am watching tv shows and movies. I decided to go into my picture settings and turn it off, and was happy with the results, however, a few minutes in the screen flickered and it came back on, on its own. I then turned if off again in picture settings and it came back on again a few minutes later. Is there anyway to turn auto motion plus off and not have it come back on, until i turn it back on again. I get if it comes back on after i turn off the tv and back on, but not in the middle of watching a dvd or a tv show. Thanks for the help.

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