Hi, I've got a white macbook 2.16ghz intel core 2 duo, with a Apple Mini-DVI to Video Adapter. I wanted to use my tv (which is very old, analog-style tv) as an external monitor. I have hooked up the cables and mirrored my computer fine under 480i, but when I unmirror the display the tv begin to shake (the picture has lines that move continuously down the tv and the color goes to white and black). I wanted to use the tv as an extension of my computer monitor, what is the problem, is there anything I can do other than buy a new tv/monitor? Thanks