Ultranet
What it is:
A proprietary protocol from Behringer for transmitting up to 16 channels of 24-bit audio over a single CAT5/CAT5e cable.
Hackaday
How it works:
Uses CAT5 Ethernet cabling but not true Ethernet networking — it’s a custom audio signal over twisted-pair.
Hackaday
Works with classic gear like Behringer P16 monitor mixers, Turbosound iQ speakers, and compatible mixers.

Not a general-purpose networking standard (e.g., can’t route arbitrarily like Dante or AES50).

VBAN, The VB-Audio Network Protocol,

VBAN Protocol has been designed for real-time transport of digital audio stream in IP-based network environments. VBAN allows to send or / and receive audio to / from other computers of any local networks. Voicemeeter already allows easy way to manage several incoming / outgoing streams.
For Any Local Network Infra-Structure

Based on UDP Protocol, VBAN is made for Audio Pro and Audiophiles, to transport multichannel audio in native PCM format (all sampling rate supported). Developed like a “RADIO” transmitter / receptor system, the VBAN protocol can also broadcast other data (Serial, TXT…).

Not sure about the mic input part. But I use Plex to host all my media and it plays locally when I’m at home and then I play it remotely as well. Have a few users that also access it. There are other options out there, but that’s the first thing that comes to mind…..works beautifully.

GC Cobb the plex server and clients will eventually freak out without internet access. Jellyfin works pretty good offline. At home I run plex but when on a road trip I toss jellyfin onto my steamdeck so my spawn can access it on their phones.

Corey Allen that can all be mitigated with some setup. Plenty of info regarding how to set it up for when the internet is down. Whilst jellyfin and Emby are solid options I’m a Plex fan. It is what my family uses for about 90-95% of our media consumption and I use the dedicated music app (Plexamp) daily as well.

BUTT to an icecast2 server on a pc or raspberry pi.

Get yourself a Dante converter and dante switch and you can take an analog moxer and run whatever sources into it, mp3, xlr, TRS, whatever but dante is not ethernet keep in mind so you need to convert it back at the other end or have a dante interface.

If you just want it to stream via the network just google network media streaming devices and take your pick. Personally for a stream,I use the extron SMP line

DANTE or OBS

VBAN : https://vb-audio.com/Voicemeeter/vban.htm

OBS and its free

https://icecast.org/download/

Distribution of audio and video signals over data networks, also known as AV
over IP (AVoIP) or networked AV, potentially offers significant benefits for pro
AV systems integrators and end users. Compared to traditional systems for AV
distribution, networked AV systems can be designed with virtually unrestricted
scalability and flexibility, in addition to the convenience and cost efficiency
of standard data networks. The benefits of AVoIP can especially be realized
in large installations for enterprises and other organizations.