I am experiencing a weird problem with my Fasttrack Ultra USB in SONAR Producer 8.5.3. During playback, at any given time and with no real consistency, the output will suddenly be invaded by a loud crackling/distortion problem that responds to the content of the tracks in a fashion I would liken to what it would sound like if the speakers were blown... For example, percussive elements like kick drum will generate changes in the crackling in sync with the beats, and the intensity of the crackling follows the overall intensity of the output. If I stop playback and restart, the crackling may or may not come back (though it is quite frequent.) I experience this with different projects, different instrumentation, different effects, etc. I've got the latest version of the software for the Fasttrack and for SONAR. It is really disruptive to my workflow and I'd love to know if anyone has any suggestions. System details below.