AFAIK, FCP is based on Quicktime, and thus can't handle 5.1 audio (yet. Rumor has it that the next version of QT will handle multi-channel). Why do you need to go back to FCP? If it's for DVD, you could export 6 AIFF files , and then send them to be encoded via Dolby Digital or DTS, or you could do layback to a tape format (al la DA-88) that can handle at least 6 tracks. Hope this helps. Christian Dolan