blocky artifacts in premiere pro (firewire capture)

[GRUMBLE]

ok, i just captured a long movie from my panasonic dv cam using firewire.
but then in premiere it looks very bad.

here is a screenshot:
http://www.embege.com/misc/roland.jpg

my system is a P4 3Ghz 512MB RAM, a GF4 Ti4200 and im using a dual monitor setup, if this could be of interest.

thanks a lot for any help to solve this issue.

edit: oh, i should add that the video looks ok when played in a normal player, like windowsmediaplayer.

[bugster]

There is something seriously wrong with the preview in Premiere. Try un-installing and re-installing it (Premiere that is).