I was analyzing a few days ago the possibility of having an option in TeamSpeak to disable the use of IPv6 in it.
I mean, is there some people that want to have IPv6 enabled for the browsing, another stuff, but dont want to use it in TeamSpeak.
This is generally speaking the hosters decision. If the server is only listening to IPv6 the client can not simply connect to IPv4 cause there is no server. If the server listens to multiple it is a DNS decision.
If both A and AAAA records are set the decision is up to the client, yes.
But a user that really needs to differentiate between the two and which program uses what should not rely on the programs itself but rather on firewall(s).
So, just disallow TeamSpeak to access IPv6 in your firewall settings.
The TeamSpeak Server can be configured not to listen for IPv6 connections. However, The best way to do this is creating a sub-domain with a DNS A record only. If the TeamSpeak Client can’t find an AAAA record for the domain, it won’t try to connect using IPv6.