yup, check that the timing master is your sound card...
then make sure that any other audio gear you have is slave syncing to your sound card.
then make sure that your soundcard isn't recording in 48khz and playing back in 44.1khz.
also when you are recording, make sure that cake is either in sole control of your audio drivers, or that it plays well with anything you have running (although i think that option only comes in sonar).
then make sure that you have caching disabled. since audio is streamed from disk to app, you don't want read caching activated.
if nothing else seems to work, make sure that your sound card isn't sharing with any other peripheral.
if it stills seems to stutter, then investigate the following:
1) faster hard drive.
2) more memory
3) better sound card (this might be 1 and not 3, but i've never used SB)