I give up for now
I'm going to purchase a cheap 5.1 receiver off of EBay for use in my basement. I tinkered with the NR-900 last night and I can get audio through the front right channel and the zone 2 right channel only. I cannot get a proper stereo sound so I give up for now. It's too bad because I had forgotten what a solid, fully featured receiver it was.
Ohio, good luck. Hopefully, your service provider will be more familiar with that model and it will be an easy fix.
Thanks