I've been running a #RaspberryPi B+ with a #HifiBerry #Amp2 in an old speaker box, for some time now. An update to the OS was needed and I found HifiBerryOS. Moved the Amp2 to a Raspy 3 and flashed it. Great option for the dedicated Sound Raspy. Spotify Streaming, AirPlay, Radio Streams and other options work out of the box. Have not been playing around a lot yet - but it looks promising.
https://www.hifiberry.com/shop/boards/hifiberry-amp2/
https://www.hifiberry.com/hifiberryos/ 🔊🎼🎶