almost black and white picture xvid, divx and dvd

[detrunks]

Hope someone can help!
I installed k-lite codec pack, zoom player and cyberlink dvd. Everytime I play an avi file via zoom it plays back in almost black and white - the same file is displayed in full colour via windows media player. WMP won't play my dvds so I use cyberlink - but it plays it back in almost black and white!!!

I have the latest drivers (including nv 6600) and the OS is X64.

Any idead wots going on???