Cakewalk Pro Audio 9: Some Audio Tracks Out of Sync

I'm using Cakewalk Pro Audio 9 -- intended for Win98 -- on an Inspiron 6000 (Win XP Pro / 1 GB RAM). For the most part, it runs perfectly fine, except that random audio tracks will intermittently play back out of sync (IOW, not always the same tracks, not all the time). If I stop & restart playback -- sometimes 2-3 times -- they'll usually sync up. This never happened on my old K6/233 running Win98.

For a sound card, I'm using an Echo Indigo IO (PC card), and I have WinXP set to give preference to background services rather than programs.

Any ideas on how to solve this?

Thanks!
--
Jim