self-hosted VS Mumble

You can fully self host it (server and everything): https://github.com/revoltchat/self-hosted

This is for folks that want a self-governed / "no big brother" Discord alternative, it's quite nice for that purpose, but it's lacking the Discord integrations (audio chat, etc.) that make it better for gamers.

Revolt looks interesting. I see they have a self-hosted repo too with docker images.

Have you checked out Revolt? https://revolt.chat/ I think you can self-host this one https://github.com/revoltchat/self-hosted

Everyone can host a Revolt instance as it's open source (the developers even published a script for Docker to make things easier), so you can even own and host a server. However, the official server is managed and owned by team members (and the main server is hosted in Germany, while media server is hosted in Lithuania according to the privacy policy).

Revolt aims to be an open source Discord alternative, looks like it would fit your use case

Not familiar but they seem to allow self hosting: https://github.com/revoltchat/self-hosted

I'm having the same problem! Saw someone opened this issue so hopefully we get a response soon.

I think Sonobus is overkill. I suggest you look at a couple of relatively old-school gamer voice chat tools - Mumble or Teamspeak. Mumble is open-source and the connection is always encrypted, Teamspeak is commercial but the free tier should be fine for you - but you have to make sure to manually turn encryption on yourself. It has been a long time since I used either, so I don't know which is easier. Both of them require you to run their matching server software.

Mumble's latency is unbeatable imo, it's basically their main focus and shows.

The sticking point for me is the lack of persistent messages, something the devs strangely think is a privacy plus. Issue open since 2016: https://github.com/mumble-voip/mumble/issues/2560

If you drop out for a minute you won't have access to anything that was posted in chat, which makes it useless for anything other than voice only comms, that might suit some business purposes but I've always needed to post links or screenshots in chat during meetings.

There's any number of alternative chat applications available, like Element, Mumble, Teamspeak etc.

Mumble?

I think Mumble might fit what you're looking for. It's been a very long time since I've used it, but it seems to still exist: https://www.mumble.info/ - I've used previously for exactly what you're describing, events with lots of crew dispersed around and no budget for radios. I had it installed on an AP running OpenWRT so it was just a case of plugging that in and getting people to install the app and connect to it.

Along with the options already mentioned, if you're not into TeamSpeak, there is an open source alternative called Mumble which operates in the same manner. No internet required, and is supported on multiple platforms.