Weird latency problem with playback

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I recently acquired a copy of Cubase 2.02. (My buddy got a copy of Cubasis I think with his sound card, and managed to make a deal with Steinberg to upgrade. He never used it, so he sold me his copy.)
I've been using a Roland VS-890 for all of my recording, and I'm ready to transfer all of the tracks to my computer. I've been using the MIDI port in my Sound Blaster Live 5.1 to sync the recorder and Cubase, and S/PDIF-in with my Delta 410 to transer two tracks at a time.
I've managed to set my hardware and software up for the synchronization... everything works, except...

When I playback in Cubase, even with a brand new clean project, there's a slight jerk/pause. Like, it plays, and then around 2.4 seconds into it it jerks, then continues like normal from then on. I've tried playing around with the different ASIO drivers. I had some luck with the Full Duplex one, but only when using the SB inputs. (Once I switch my input buses to use the S/PDIF in the same singleton jerk happens.)

Any help is much appreciated.

(edit)
ah yes, my system specs:
Athlon XP 1800+ (1.53ghz)
768mb DDR ram
60gb hard drive 7200rpm with about 8.5gb free (and my Windows XP installation is on a seperate partition)