Additional features, settings, or issues not covered by specific Microsoft Teams categories
Hi Tau,
Thank you for posting. You can use Call Analytics that helps you troubleshoot call or connection problems with Microsoft Teams. Call Analytics shows detailed information about the devices, networks, and connectivity for the calls and meetings of each user in your Office 365 account. Call Analytics can help you figure out why a user had a poor call or meeting experience See Use Call Analytics to troubleshoot poor call quality
For your reference: Call Analytics and Call Quality Dashboard
You may also refer to the article for prepare your network for Teams: Prepare your organization's network for Microsoft Teams
Moreover, ensure that ports and addresses listed mentioned in the article for Teams are reachable. See Office 365 URLs and IP address ranges.
Your time and understanding will be highly appreciated.
Best regards,
Shyamal