Problem with video playback - fine lines on screen

[amw3465]

I've noticed a problem when playing back any videos with VLC, Totem or flash videos on a web site (I've not tried any other media players). What I see is very fine lines (usually one or two). They don't appear in every frame but it is noticeable once you spot them, not easy to spot in a small window but full screen its worse. I've attached a screen print of an original dvd which you will see two lines breaking up the video, what I actually see on screen is smooth video which is of very good quality and high definition but I do see these two lines running across the screen very quickly. I'm using Ubuntu 9.04 Beta with compiz on and I'm using the nvidia drivers version 180. My card is the nvidia GT9500 1 gb onboard memory bought new 6 weeks ago, so I assume my card is not faulty and should be powerful enough to watch a DVD in full screen. When I used Ubuntu 8.10 this also happened but when I used Ubuntu 9.04 alpha 6 I never experienced this problem or at least it wasn't as noticeable. If I turn compiz off then I get no video playback problems.