I’m running Mopidy with web interface to stream to multiple audio output devices (like my receiver in the living room) using Snapcast on Pi’s (some with HiFiBerry module) over the network. Mopidy also integrates nicely into my workstation with KDE using MPDRIS and a local Snapcast server.
This works for both my music collection and some webstreams. I’m quite happry with this setup.
Apparently TrueNAS are building FreeIPA support in their next release. It is currently in beta and I’m waiting for the release to test it.