AndrewS,
One thing I can tell you. If you are listening to a stereo source with a stereo surround mode selected (Stereo, Bypass, or Upsample) you can not adjust the sub via the "Channel Calibration" menu. This threw me off at first as well until I figured out to make adjusments in a 2-channel surround mode, you need to go into the "Surround Config" menu and use the 2-channel offset level and you will then hear a difference.
When calibrating for a surround mode (DD PL2x, DTS, etc) you CAN and should adjust the sub level through the "Channel Calibration" menu.
I may be ble to help you more. I had 2 SVS 20-39CS+ subs hooked up to my 990 at first. Tell us which model you have. I am assuming they are passive.
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Doug
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