Yeah, Drew; what you later "pointed out" wasn't apparent from your first post, and it was thought that you meant that the volume number couldn't go above -8. As it turned out, this had nothing to do with the calibration, by Audyssey or otherwise. Good that you found the "intelligent volume" setting problem.
Yes, although Audyssey set the fronts to full range because the measurement showed that they were able to reach low enough, it's still a good idea to give the sub more work in the frequency range that it does best and take some of the lowest bass load off the M80s. Manually set the M80s to an 80Hz crossover.
