I only have the Red Octopus disc, and at the moment, my 105 refuses to pass 1080p, so the menus don’t show up. (Working on the problem, I’ll keep those interested in the loop) There’s a short, repeating loop from track 1, and if I press OK on the remote, it starts playing a surround of track 1, then track 2…, all the while my screen is complaining that it has no signal and I need to check my HDMI connections.
I’m using the analog audio outputs from the 105 into my Marantz 7701, with HDMI (of course) for the video.
Boo! that sounds like a whole mess of Not Fun.
I'm wondering if the weirdness you are experiencing is because of some weird HDMI handshake issue?
I have noticed some oddness with my own 105 myself, mostly because now I'm using it more because I've been listening to these quadios whereas previously I was primarily either streaming Qobuz or else using Fire Stick to watch sports or movies. My current setup is Oppo -> Denon AVR-S760H -> Sony KDL-52EX700 (a ~10 year old 1080p television). What I've found is that when powering up everything (I use an old Xsight Color universal remote) when the Denon is already set to the "Blu-Ray" input and there's a Quadio disc in the player, the screen is magenta colored and I have no sound, what looks like a failing HDMI connection but I believe that it is actually a failed handshake (and the cable from the Oppo to the Denon is a new, good one because for a while I was using a 4K TV in the living room. I also had issues with the Sony 4K player that I tried to use, but I digress)
How I can get it to work is to change the input on the Denon to anything else, then switch it back to Blu-Ray. I don't have this issue with other HDMI devices, even ones that change their output resolution/frame rate, so I don't really have an explanation for it, but it seems that disc players in particular can cause these issues. It seems the trick is that the Oppo has to completely power up first before the Denon looks at the Blu-Ray HDMI input, then everything is OK. So I guess I have to go back to my remote program and either build in more delay or change the order of device power up around so that the Denon powers up last and maybe I'll even have it read a different input like my Chromecast and then switch to the Blu-Ray.
If I was last using a different input, like streaming music from Qobuz through a Chromecast, then everything works fine.
Of course I may be way off base here because I'm using the HDMI to pass the audio to the Denon (yes, I know that a 105 is absolute overkill for this use, but it was easier to use it than it was to mess with the Sony) and using the Denon's internal DAC whereas your setup is using the analog audio outputs. Now I have used it that way previously but have not had the specific issues you're having...
Edit: humor me, try playing the disc with the HDMI cable unplugged, see what happens.
Also if it turns out to be a fault with the Oppo, I would strongly recommend just sending it back to them for repair. It's surprisingly inexpensive and doesn't take long. Even though they're out of the business, their customer service is still great.