OK, curiosity has got the better of me and I have tried this on my old Raspberry Pi Model B!
To an extent this works OK and it’s a remarkably simple implementation, I can see this being of great benefit to people.
I use a Naim NDS and I am experiencing inconsistent results depending on the resolution of the file. Currently I can play 24/192 files OK but 16/44 files result in a static noise. If I enable FLAC compression within Roon all is well.
I note that you are actually using the same UPNPBridge software that I currently use, albeit wrapping it nicely into a plug and play solution.
I’ve seen this issue before but normally the challenge has been playing the 24/192 files and until now so I put this issue down to throughput. However on the same Pi using UPNPBridge and a lightweight distribution I was able to play most material with occasional static on 24/192 with FLAC compression set to off. It’s odd that the more challenging 24/192 files play but the 16/44 don’t.
I currently use UPNPBridge running within Logitech Media Server as a plugin in a container on my Celeron based QNAP NAS. I don’t have any issues with the static noise on this device even with FLAC compression disabled.
Why I can hear you asking don’t you just enable FLAC compression and be done with it?!
Well the NAIM NDS doesn’t sound quite as good if it receives FLAC and does the decoding onboard the streamer. Naim does explain that the overhead of doing this generates small amounts of noise within the streamer which slightly affects sound quality. Sending WAV or PCM avoids this and it sounds better for it.
Edit: The bridge allows you to send WAV if correctly configured - thanks to @DrCWO for his guidance.