Hey, you can try adobe's site, it might be addressed here.

Troubleshooting digital video playback on Adobe Premiere Pro CS3 (Windows XP)


Let me know if you find anything, I'm interested in looking into Adobe myself.
Glenn.

I had this problem, and partly found it to be the USB hard drive on which the clips were stored, an external drive. Having bought a couple of small drives (80gb) and fitted them internally the situation improved significantly, but did not entirely disapear. A jump to a 4gb RAM, 1gb graphics RAM, Quad core processor with SATA hard drives the problem has gone altogether, so I would say, irrespective of file type as I've used FLV's, MOV's, AVI, HDV and MOD files with no difference, that it's a hardware issue.

i have to agree, most of the time it is a hardware issue. i found significant differences based on which hard drive i used. using a seagate barracuda ide hard drive with 7200rpm i got jerky playback, but if instead i capture to my other seagate barracuda 7200rpm SATA the problem completely disapeared. in the past though i have also found converting clips to raw DV files first also solved the problem. hope that helps.

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