PicorePlayer is a OS for Raspberry series of small computers. It boots in 15 seconds.
It can be accessed with a web page or SSH. It has Squeezelite and a LMS server. By using several Raspberry Pi’s it is even possible to build a multiroom music system that allows for streaming synched music as well as different streams to separate rooms.
Music are streamed through a LMS server available on your network.
PiCorePlayer: https://www.picoreplayer.org/index.html
LMS is Logitech Media Server (formerly SlimServer, SqueezeCenter and Squeezebox Server).
PiCorePlayer supports Pi-DigiAMP+.