Try these checks in order:
- Make sure the microphone is not muted in the call app. In Skype for Business, scheduled conferences can mute participants automatically. Unmute by selecting the microphone icon in the call window.
- Check the microphone hardware.
- If using the built-in microphone, make sure it is not muted.
- If using an external microphone, make sure it is fully plugged in.
- If using a wireless headset, make sure the battery is charged.
- Check for a physical mute button on the headset or cable.
- Select the correct microphone device.
- Open Audio Device Settings.
- If needed, choose Custom Device.
- In the Microphone drop-down, select the microphone to use.
- Speak into it and check whether the blue speech activity indicator moves.
- Check microphone level in Windows.
- Right-click the speaker icon at the bottom-right of the screen.
- Open Recording devices.
- Right-click the microphone being used and select Properties.
- On the Levels tab, increase the microphone volume or boost if available.
- If others hear poor or broken audio rather than no audio, check the connection. Gaps, delays, robotic sound, or dropouts can be caused by the internet connection.
- If using a call app on Windows and the microphone works in other apps but not this one, check microphone privacy permissions. In Windows, go to Settings > Privacy & security > Microphone and make sure desktop apps are allowed to access the microphone.
- Make a test call if the app supports it. If the recorded playback can be heard, the microphone is working and the issue may be with the other participant’s playback device.
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