My requirement was entirely unnecessary and nice-to-have, I arrived at it like this:

- it would be great to make use of that old AV amp and random collection of speakers (I upgraded the living room surround last year)
- it would work really well on my games PC
- hmmm, can't find any toslink cables
- bugger, my PC doesn't have a coax out
- hey, I could try HDMI, I have a completely unused Intel GPU with an HDMI port
- yippee, it works and I get uncompressed audio, bonus

They came "I wonder if I can get Windows not to extend the desktop over there".