I had to turn the gain down nearly a 1/4 turn on my DSP3400 as I was getting readings of -12db or something similar on the sub.It is now within 1-2db. I can't help but wonder if there is some other problem here. I am using a Denon 2809, virtual twin of the 989, and whether I have my fronts set to large OR small, turning my Denon to +7 on the volume is painfull if you're anywhere near the system.
As Doc says, you should dial the gain back on your sub a little...try an 1/8th of a turn to start, try running Audyssey again to see what the new setting is for the sub. It should move closer to "0". Make further adjustments if necessary, it doesn't have to read "0" but should be much closer than "-11.5".
