when I had my ep500 set at 9 o-clock audessey set my sub to -12db.

I changed it to about 6 or 7 o-clock and now it is at -2.5 db (that is still about 4-5 db 'hot' when compared to my other speakers)

I would try adjusting the distance of the sub in the receiever as well.

also, try flipping the phase switch on the subwoofer.

-David