A way to stream any digital audio signal to Chromecast Audio?

Question

I'd like to know if there is any known way of streaming a digital audio signal (say optical or coax) from a household stereo item like a cd player INTO the Chromecast Audio device for house-wide streaming?

Solving this would basically mean I could stream any digital media from existing sources, which would be awesome.

AFAIK the Chromecast needs an application to feed it a stream, but maybe there are third-party apps that does this today, say for instance in conjunction with Raspberry Pi or something?

Answer 1

I'll add an interim answer of my own based on some researching. I have not tried this out yet, but maybe it can help the next adventurer.

1. Get a sound card capable of capturing a digital (and/or analog) signal and feed it to your computer via USB, such as ESI U24 XL (Linux compatible) and hook it up to your source.
2. Get a Raspberry Pi (or just any smallish computer really that fits in your hifi rack) to run Linux.
3. Set up ALSA to create a FIFO (a pseudo-file) that outputs the captured data (on say /tmp/mycdaudio.wav.
4. Set up PulseAudio DLNA to stream to your Chromecast
5. Get something to play the FIFO so that the stream is picked up by PulseAudio