1. Check that your microphone is not muted.
2. If there is any background noise, move to a quieter area.
3. Check if the issue is happening with a specific phone number on outgoing or incoming calls.
4. Connect a compatible wired headphone that has a microphone. If the headphone works, remove them to continue troubleshooting the internal microphones.
5. Restart your phone and test if your audio is working, select one of the options:
- Option 1 - Record a new voice note, select Start > Messaging > New (+) > Attach and tap voice note to start recording. Tap done and play the recording. If you can hear the recording, your microphone is working.
- Option 2 - Test your outgoing audio by making a Skype test call, start Skype app, find Skype Sound test service (echo123) in your contact list and tap call.
6. If the problem persists, locate your phone's microphones and check that openings are not blocked. To find the microphone openings, see your phone's user guide or search online to find the chapter: Explore the keys and parts of your phone.