Thank you for posting your question on Just Answer! I will be happy to help you with this problem. Can you please give us some more information so I can better answer your questions.
-Can you verify the model number for the television? (this can be found on the back of the unit)
-How old is the unit?
- Do you have this problem while watching all different devices hooked to this television? (DVD player, cable, satellite, game counsel, ect.)
-If you press the menu button on the tv itself does the menu show?
-can you describe these lines? (what color, how thick, how many, left to right or top to bottom, ect.)
Please give me this information and I will be happy to assist you further.
Near the top or the bottom do you have any horizontal lines at all? even just one?