The player has full 7.1 analog output but your amp doesn't have the appropriate inputs, either digital or analog, from what I see in
its manual, it's more about matrixing 2ch to multi-ch audio than simply passing it thru from what I see.
I think it's simply time for a new 7ch avr with the amp/features you need to complement your 7.1 speaker setup so you can get all there is on that blu-ray disc. Even with your optical connection you weren't getting that....you need hdmi for that.