I was able to resolve this. I’m using a Sony UBP X-700 Blu-ray player. I had to change the digital audio output from auto to PCM. Then I had to change the CORSAHD device from “copy” which was passing through the audio to Atmos/7.1 content which made it multichannel PCM 7.1 for a DTS-HD 7.1 track.
Previously when the Blu-ray player was set to auto, flipping the switch to Atmos/7.1 gave me an unsupported audio notification in the Sonos app and no sound. After switching the Blu-ray player to PCM, I was only getting stereo PCM when leaving CORSAHD as “copy”/passthrough. I had to activate the Atmos/7.1 switch to get multichannel PCM 7.1. Hopefully I’m actually getting 7.1 and not some kind of upscale of stereo PCM, but it sounds accurate on my surround speakers.
So overall, this CORSAHD device gives you everything Arcana can do at a fraction of the price and even includes multiple HDMI In ports that Arcana does not. However, it does require some settings changes to toggle bewteen Atmos, DTS-HD surround and stereo, but I’m willing to live with that. I have a 2017 LG TV in my bedroom without eArc which required this. I expect all TVs to have eArc going forward, so I suppose this information will be useful to some people for a little bit of time until the necessity of Arcana/CORSAHD becomes obsolete.
