It’s just a note:
If someone is using an Antivirus/Secure XYZ Suite application try to disable Web Protection scanning HTTPS.
Most Web Protection application install their own SSL root certificate to inspect the HTTPS traffic, who act as middlemen, this can lead to such errors/problems.
EDIT:
# openssl s_client -status -connect clientapi.myteamspeak.com:443 -tls1_2
---
Verification: OK
---
New, TLSv1.2, Cipher is ECDHE-ECDSA-CHACHA20-POLY1305
...
Protocol: TLSv1.2
Cipher: ECDHE-ECDSA-CHACHA20-POLY1305
...
Verify return code: 0 (ok)
---
closed
No TLS issue, is on your side.
~SxSeth