hidden carefully inside loxones music server is squeezebox with some custom wrapper.
take a look at musicserver4lox
https://www.loxforum.com/forum/projektforen/musicserver4loxuse chrome to translate
its basically logitech/squeezebox with some software to give feedback to loxone such as volume, whats playing, mode etc and also has facilitites to integrate doorbell, text to speech etc
it also allows you to link idevices so i can play from my phone to a zone, and uses a line-in on the audio to play from my record deck
and it can use chromecast, airplay and dnla (sonos) devices as additional zone players so they all become integrated
it uses cheap usb sound cards to create multiple zones - each can be mono, stereo or more channels, and links in with existing squeezebox hardware
i used a reconditioned i7 dell laptop (ebay £240 with a year warranty)
2 x usb sound card for 16 mono channels (£40)
12 ceiling speakers, 1 per room for 12 zones
a dayton audio multi-channel amp (same as loxones, but 60w/ch rather than 40w)6 stereo channels = 12 mono zones (£500)
9 logitech hardware players (1 boom, 6 radios, 2 duets) - all from ebay around £70 per radio and £70-£100 per duet including hand remotes which are great
and a long press on the kitchen light switch sends a text to speech message to a group of zones to tell everyone to come down for dinner - thats the best bit according to my wife.
the squeezebox server scans my itunes folder every few hours so the whole house has access to all my itunes music and playlists, which i use on a PC for easy music management. It also has a spotify plugin so any user has access to that as well.