See if moving the component wires away from the other cables solves or changes the lines on the screen. If it does then it is likely poor shielding on the cables. Can you try hooking the 360 up to another display with the same component cables to see if it is different on that display? If it is not an issue with a different HDTV (must be HD to have the component connection) then it is likely your TV, but if the problem exists it is likely the 360 or the cables.
Try buying new component cables also as a troubleshooting option also.
Good luck!
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SA 3250HD
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