I haven't heard of this problem before, and it doesn't appear to be in the bug list yet.

If anyone has a song file that consistently exports with an extra noise at the start, please send the song file and the WAV file render of the Drums track with the extra noise to support@pgmusic.com.

Please include a brief description of the issue (and/or a link back to this post), and the exact version and build of Band-in-a-Box that was used, I'll see if I can replicate the issue and report it to the development team.

Thanks
Kent
PG Music