Be Aware.. I have a 7.1 Output in my I/O. When using a 5.1 Bus & mapping to the 7.1 Output you lose the Rear Surrounds. If you create a 5.1 Output & Map your 5.1 Bus to that it works fine. Sat with a Dolby Specialist & diagnosed this..There is a bug when mapping to the 5.1 bus of a 7.1 output.