Voice server hosting

Discord took most of this market, and most game hosts quietly dropped voice hosting with it. These are the ones that still sell it — usually per slot, usually cheaper than a game server, and worth it if you want a channel nobody else moderates.

Why rent a voice server at all

Discord is free, and for most groups that settles it. The reasons people still pay for a voice server:

You own the moderation. Nobody can suspend your community because a platform changed its rules.
Lower latency, if the server is near you. A TeamSpeak server in your own region usually beats a Discord voice region you cannot pick.
Slot-based pricing is cheap. Voice servers are billed per slot, and a 25-slot server costs less per month than most game servers.
It runs beside your game server. Several hosts on this page will put both in the same datacentre.

What to check before you buy

Slots, not players. A "50 slot" server means 50 people connected at once. Buy for your peak, not your average.
Which platform. TeamSpeak 3 is still the most widely sold. Mumble is free and open-source and a few hosts sell it managed. Ventrilo is largely legacy at this point.
Location. Voice is far more sensitive to latency than it is to bandwidth. A server on the wrong continent is audible.
Licensing. TeamSpeak servers over 32 slots need a licence; ask whether the host holds one or whether that becomes your problem.