If you find that you’re having issues with call connection / quality on your Yealink, the following config lines may be the answer that you’re looking for:
account.1.sip_server.1.transport_type = 2
account.1.sip_server.1.port = 5061
account.1.srtp_encryption = 2
account.1.codec.opus.enable = 0
account.1.sip_server.1.expires = 1800
Please note, these config lines will:
Enable TLS
Set the port for TLS
Allow the phone to use encrypted calls when needed
Disable OPUS Lower SIP registration times/timeouts
For guidance on how to set up config lines through your Yay Dashboard, please refer to the FAQ here, which will also provide you with many other useful config lines for Yealinks.