Certainly, as George points out, the Oppo can select audio tracks on the disc like any other Bluray player. Not sure, however, if one can change the audio tracks 'on the fly' to allow a useful A/B comparison. I was thinking that if
I also connected the standard SPDIF digital audio ouput to my 861 that I could more easily compare just by switching phantom inputs.

My Kit: 861v8+ID41, 800v4, UHD722, MD600, MS600, MS200, Oppo BDP-203, Genesis 201, Genesis 350 SE, Genesis S4-8 Sub, BG 520i, VTL MB450 II, Krell Showcase 7, Genesis 928 Subs, Danley DTS10 sub, SVS Ultra 16 subs.