When playing the speaker assignment audio test, the subwoofer channel does not make a sound, however it does when using the amps test tones, and it certainly works during normal use. The sub/sat package is tannoy fx5.1, with the sub set to come on at 200hz. I believe it goes down to 45hz from the specs. When using the sub crossover test that sweeps down from 200hz to 20hz, it sounds fine; but I am just intrigued why it does not come on with the THX test tone - does it play at a level lower than 45hz? Any ideas?