I wish they'd make some USB controlled extra inputs like a coax/toslink input switcher to stack with the ultras and integrate with the control app. If you don't use the ARC input there's the Sonos toslink to ARC adapter which should work, though I haven't tried it.
It's been my experience with an Ultra. I don't have an Amp Ultra to try it with, hence the assumption. I guess the AI in your search was hallucinating.
Switchers for each are a thing, very cheap. More for including auto-sensing and both in one.
You cannot use the USB port on WiiM Amp Ultra or WiiM Ultra as digital audio IN. It is only usable for attaching storage or for digital audio OUT (WiiM streaming to an external DAC, not acting as an external DAC for a different digital source, such as laptop). The competing Eversolo Play does have this ability, but its integrated amplifier is likely to be less performant (based on the fact that far more expensive Eversolo Amp F2 is outperformed by WiiM Amp Ultra).
Correct; you can use a USB DDC with your source that has USB out to convert to Toslink. Cubilux makes inexpensive ones, or you could get something like a Douk U2 (Pro).
That does not guarantee bit-perfect output, it only guarantees no separate digital volume attenuation, but turning on ReplayGain, using RoomFit or (P)EQ will still, “change the bits,” even with volume fixed. Any internal resampling will also, “change the bits,” even with volume fixed, such as trying to play DXD or DSD material.
Also consider that many devices internally have more bits available than the original encoded audio. If the track is -let's say- 16 bits, you can use the rest for volume control without modifying the "bit perfect" stuff, so you can have both.
Purists hate this one weird trick...While true, "bit perfect" is not necessarily synonymous with "best possible sound".
Are you speaking for all of them?
It's a joke/meme. I agree that many take the bit-perfect issue way too far.
Sorry my smileys were ignored when I posted from smartphone. I know you know, was tongue in cheek!
If you have the output volume of your WiiM streamer at 100 but the volume limit at 80 %, then the output is not bit perfect, of course (if this was your previous question). Does this matter? I don't think so.
"Big Butt" Lester has been referring to the physical optical input. The optical input has no concept of what is currently playing. There is no meta data contained in the S/PDIF signal. This is the same for all optical inputs on all devices.
