I'm sure JohnK or someone else will be along soon. Again, if you can configure the 990 to act as just an amplifier, and ignore the preamp section it might work. I would think you would just hook up the the AVR preouts for the front L/R channels to the HK amp inputs using RCA interconnects, then run speaker wires from the HK to the M80's. The other speakers would be hooked to the AVRs standard speaker posts.

Again, I could be way wrong.

M80s VP180 4xM22ow 4xM3ic EP600 2xEP350
AnthemAVM60 Outlaw7700 EmoA500 Epson5040UB FluanceRT85