Video Camera or Audio not working in MS-Teams

Another common issue in Teams troubleshooting is failure to detect the video camera or audio during video conferences.

Webcam Solution 1: Make sure Microsoft Teams has permission to use the video webcam

1. Press the Windows key +I
2. Go to Privacy.
3. Select Camera.
4. Make sure that Allow apps to access your Camera is activated.
5. Also, make sure that Choose apps that can use your camera is activated for Teams

If it is already on, turn it off and leave it for a few seconds before turning it back on again.

Webcam Solution 2: Update camera drivers. Another common reason for why a camera is not being detected is old camera drivers.

1. Open your Windows search bar.
2. Type Device Manager.
3. Select one of the categories.
4. Right-click on the device you want to update
5. Then select Update Driver.
6. Windows will scan and update the driver if it finds a newer version.

Audio solution: After trying the above, it may be helpful to change one of your privacy settings.

1. Open Settings
2. Under Privacy, select Microphone 
3. Make sure the setting for Microphone access for this device is turned On. If the setting is already turned on, turn the setting off then back on again
4. Close all applications and restart your device

Reference/s: https://www.ir.com/guides/microsoft-teams-troubleshooting-guide