I think it is strange that so many people have problems with the 350. I owned one for over a year before upgrading to the 500. If I recall, the volume (gain) on the sub was 11-12 o'clock, which put the Denon levels for the sub channel around 0dB. Crossover on the sub was cranked to the maximum, since the receiver was managing at 80hz. I also kept everything set to small.

Never had a problem with the 350 going to sleep on my Denon 2805 which is an older model.

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