Problem displaying all video material
 

Hi,

Win XP SP2, regularly updated.
Geforce 6800 with recent ( april 2009 ) drivers

When I try to dislpay whatever video ( mpg / wav / wmv / DVD) I allways get
an image with small vertical lines ( like this ||||||||||||||||||)
surerimposed and flickering.

Any idea how I can find:

- why ?
- how solve ?

All these videos have been displayed ok on other PCs

I have installed the latest KLite codec pack