Check your picture settings under 120 HZ if there is a custom setting you can adjust jutter.
I purchased the Samsung LN40C670 two weeks ago at Best Buy. Initially, no problems. On Sunday, I noticed a "jutter" in the picture. The jutter is up and down and quite pronounced. It only happens when I set the video output to 1080i. No issues with 720p. I don't have a blue ray player, so I cannot check that. Any thoughts? Could it be the cable box? Thanks!

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