Poor call quality in Teams after a license change is a common issue. You may hear choppy audio, see frozen video, or experience dropped calls. This usually happens because the new license lacks the correct audio and video conferencing capabilities. This article explains the root cause and gives you clear steps to restore call quality.
When you change a user’s license, Teams may not immediately apply the new service plan. The client can keep using old settings, causing degraded media performance. You will learn how to verify license assignments, check network readiness, and force Teams to refresh its configuration.
Key Takeaways: Restoring Teams Call Quality After a License Change
- Teams admin center > Users > Active users > Licenses and apps: Verify the correct service plans are assigned to the affected user.
- Teams client > Settings > Devices: Reset audio devices and disable hardware acceleration to improve media reliability.
- Windows Settings > Apps > Microsoft Teams > Advanced options: Use the Reset and Repair options to clear cached settings that may be stale.
Why Teams Call Quality Drops After a License Change
Teams relies on service plans assigned through your Microsoft 365 license. These plans include Microsoft Teams, Phone System, and Audio Conferencing. When you change a license, the new service plan set may differ. If the correct plans are not applied, Teams may revert to a degraded media mode.
The Teams client caches the user’s service plan information. After a license change, the cache may still hold the old plan. This causes the client to think certain features are unavailable. As a result, the media engine may use lower bitrates or skip advanced codecs, leading to poor audio and video.
Network conditions also play a role. A license change does not affect your network, but Teams may need to renegotiate its media path. If the client does not refresh, it may keep using an inefficient path. This can cause jitter, packet loss, and latency.
How Service Plans Affect Media Quality
Each Microsoft 365 license includes a set of service plans. For example, Microsoft 365 E3 includes Teams but not Phone System. Microsoft 365 E5 includes both. If you move a user from E5 to E3, they lose Phone System. This can affect call routing and media quality.
Audio Conferencing is another plan that matters. Without it, the user cannot dial into meetings via phone. This plan also affects the media path for PSTN calls. If the license change removes it, the client may fail to establish a proper media session.
Steps to Diagnose and Fix Teams Call Quality After a License Change
Follow these steps in order. Each step addresses a specific cause. Do not skip any step.
- Verify the license assignment in the Teams admin center
Sign in to the Teams admin center at admin.teams.microsoft.com. Go to Users > Manage users. Select the affected user. Click the Licenses and apps tab. Confirm that Microsoft Teams, Phone System, and Audio Conferencing are toggled on. If any are off, turn them on and save. - Check the effective service plan in the Microsoft 365 admin center
Go to admin.microsoft.com. Navigate to Users > Active users. Select the user and open the Licenses and apps tab. Verify that the assigned license includes the required service plans. If the license type changed, assign a license that includes Teams and the needed calling features. - Force the Teams client to refresh its configuration
Sign out of Teams completely. Close the Teams client. Right-click the Teams icon in the system tray and choose Exit. Wait 30 seconds. Sign back in. This forces the client to fetch the latest service plan information from the server. - Clear the Teams cache
Close Teams. Press Win + R to open the Run dialog. Type %appdata%\Microsoft\Teams and press Enter. Delete the contents of the folder. Do not delete the Teams folder itself. Restart Teams. This removes any stale settings that could cause poor media quality. - Reset audio devices in Teams settings
Open Teams. Click your profile picture and select Settings. Go to Devices. Under Audio devices, change the speaker and microphone to your preferred hardware. Test the call. If the problem persists, disable hardware acceleration. In Settings > General, uncheck the box for hardware acceleration. Restart Teams. - Run the Windows network diagnostics
Open Windows Settings. Go to System > Troubleshoot > Other troubleshooters. Run the Network Adapter troubleshooter. This checks for common network issues that affect Teams media. Also run the Incoming Connections troubleshooter if available. - Use the Teams call quality dashboard
In the Teams admin center, go to Analytics & reports > Call quality dashboard. Look for the affected user’s sessions. Check for high packet loss, jitter, or latency. If you see issues, the problem may be network-related. Contact your network administrator to fix the connection.
Alternative Method: Reset the Teams App
If the cache clear does not help, reset the Teams app at the Windows level. This is a deeper reset that clears all app data.
- Open Windows Settings
Press Win + I. Go to Apps > Installed apps. Find Microsoft Teams. - Click the three-dot menu and select Advanced options
Scroll down to the Reset section. Click the Reset button. Confirm. This clears the app’s data and settings. - Restart Teams
After the reset, Teams will ask you to sign in again. Sign in and test a call.
If Teams Still Has Poor Call Quality After the Main Fix
Teams Shows a Black Screen During Video Calls
This often happens when the GPU driver is outdated. Update your graphics driver from the manufacturer’s website. In Teams, disable hardware acceleration as described in step 5. This forces the CPU to handle video rendering, which is slower but more reliable.
Audio Echo or Feedback in Calls
Echo usually comes from the speaker being too loud or the microphone picking up the speaker output. Lower the speaker volume in Teams. Use a headset instead of external speakers. Check the microphone settings in Windows to ensure only one input device is active.
Calls Drop After a Few Minutes
This can be caused by the network firewall blocking Teams media ports. Teams uses UDP ports 3478 through 3481. Ask your network admin to allow these ports. Also check if the user’s VPN is interfering. Disconnect the VPN and test again.
New Teams Desktop vs Teams on the Web: Key Differences
| Item | New Teams Desktop | Teams on the Web |
|---|---|---|
| Media engine | Uses the full Teams media stack with advanced codecs | Uses browser-based media with fewer codec options |
| Hardware acceleration | Can be disabled in settings | Controlled by browser settings |
| Cache behavior | Local cache that can become stale | Browser cache, cleared by clearing browsing data |
| Call quality diagnostics | Available in the call quality dashboard | Limited to browser network logs |
Conclusion
After a license change, poor call quality in Teams can be fixed by verifying service plans, clearing the cache, and resetting audio devices. You now have a clear sequence to restore normal call performance. Start with the Teams admin center to confirm the license assignment. Then clear the Teams cache and reset the app if needed. For persistent issues, check the call quality dashboard and network ports. Use the New Teams desktop app for the best media experience.