Have you tried the THX opti-mode test that is on Star Wars 1 or T2. If you have the 1E Bass Management option set to SWFR (not main or both) then on my DSP AX630 the sub works fine during the Channel Test Tones but I get nothing out of the Sub during the 200Hz to 20Hz sweep tone used for balancing the Sub to the Main speakers. Is it just my amp or have Yamaha not conformed to something. The .1 channel works fine during those films. If I try the same test using the internal decoder on my Pioneer 626 DVD player then the .1 channel works fine during the sweep tone. This should apply to the 630, 730 & 1200 range. I would be interested to know what other owners find or even owners of other AV amps.