Please follow methods below for troubleshooting:
- Press volume up key to increase volume during a call.
- Disable "Hearing aids" function in Settings > Call Settings > Hearing aids.
- Connect your phone with a bluetooth headset to test.
- Dial another number to test if your receiver works well.
- Reboot your phone.
- Update firmware to latest version: Go to Settings > About > System update > Check Update.
- Access Safe Mode by long pressing power key > tapping and holding Power Off > tapping OK. If your phone works well in Safe Mode, there may be some 3rd apps that cause malfunction. Please reboot your phone and check again if it works well.
- Backup your data and perform factory data reset.
