MPD
Music Player Daemon (MPD) is a flexible, powerful, server-side application for playing music. Through plugins and libraries it can play a variety of sound files while being controlled by its network protocol.
MPD handles both music management and playback and does not require a secondary client to work. MPD is designed to run from a headless compute.
You control MPD using secondary devices like your mobile phone, a tablet or another computer.
Mobil or tablet:
to use mcconnect you must also enable upmpdcli on the system
other apps:
Lumin, Linn Kazoo, Linn
To use these last three, in addition to enabling upmpcli, you must also enable bubbleupnp and configure it, see the bubbleupnp section.
Mpd by default (in GentooPlayer) automatically finds the library in mnt and media, so you don't have to change anything in the configuration to search for files.
You just need to do an update of the database, from one of the client, after mounting a disc containing the music.