If you're working with H.264 video files in a Soundtrack Pro project, you may come across a situation where the audio stutters when you scrub the playhead.
This can happen if your available hard drive or CPU bandwidth is insufficient. As a workaround, try moving the video file to a faster hard drive. Hiding the video tab may also improve audio performance when scrubbing files.
(For instructions on hiding the video tab or other "how to" questions, see the Soundtrack Pro manual, available from the Help menu.)