My digital audio bridge project is finished and written up at https://rudd-o.com/digital-audio-bridge. On top of the build itself, I made the device flashable directly through the web, so there's no commandline needed to get it up and running — look ma, no commandline! I also put together an installer to go with it.
I'm building a small device that drives an LED over I²S to blast music through an optical fiber into my receiver's S/PDIF input, giving my home theater prepro proper Music Assistant SendSpin support instead of the AirPlay implementation that crashes my amp and adds up to ten seconds of latency. Because S/PDIF is digital and uncompressed, whatever Music Assistant sends arrives bit-for-bit perfect at the prepro's internal DAC rather than going through a cheap external DAC — a FLAC file really does land intact, not just in theory. The proper LED blaster is in the mail; once it arrives I'll solder everything up, put it in a tiny box, connect it to the receiver, and we'll have 100% digital room-synced streaming in the living room. The idea came from a DIY Perks video, and I'll publish a full build with a blog post and files once the final parts land.