Search using the keyword "samsung lines" on these forums...you'll be surprised. I'd take the thing back asap and make sure the second one doesn't exhibit the same issue.
I just recieved my led 8000 TV about 2 weeks. I recently noticed that before powering on the cable box that 2 black lines surfaced. When powering on the cable box the lines are no longer visable. I'm worried that this is more serious than it appears. I've taken steps as, tried different HDMI cable, reseated power cord from TV, connected cable box to another HDMI connection. The black lines just won't go away. The strange thing is that it ONLY appears when I switch to HDMI port 1 of the 4 in the LED TV (the orignal connections to my cable box). Anyone have any ideas.

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