Heay mac,
Can you be more spacific with the issue you are having, also can you let us know what skin you are using... is your xp installation optimised for Mixvibes... what are you latency settings... do you experience this problem with your VCI 100 and/or vinyl/cd control, etc...
Other users have exprienced simelar problems, have a read at this post...
viewtopic.php?f=307&t=11374with more information we should be able to help you out..
regards
Bryan