When watching 4:3 TV in modes like "Just", I keep seeing this weird shimmer/rainbow effect occasionally. I don't really see it when watching higher quality content like DVDs. Since I do have per-input picture settings, is there anything I can do to minimize this effect? (Interestingly enough, my wife and friends can't see this effect at all. I'm not sure why I'm the only one that can see it, but it's driving me crazy.