There is a bug where a normalisation routine slipped into the compile. The crackling/static you hear is a result of the incomplete implementation of the normalisation. Roger said he will be releasing a fix for these types of tracks in the next release.
To fix it for now you could delete the track, sync and reload the track. A bit of a hassle, but there you are. And there aren't any guarantees that it wont happen again. If it keeps happening I believe the response is to downgrade to 1.03.