Sound does not come out of the headset.

Check the following

1. Make sure that the Bluetooth device and both the right and left units of the headset are turned on.
2. Turn up the volume of the Bluetooth device.
3. Make sure that the Bluetooth device is playing back.
4. If you can only hear sound from the left unit, check the following.
   • Depending on the smartphone app (which requires HFP (Hands-free Profile)/HSP (Headset Profile), you will hear a voice from the left unit only.
   • Voice Guidance, ringtone, and speech can only be heard from the left unit.
5. Make sure that an A2DP Bluetooth connection is made between the headset and the Bluetooth device.
6. Delete the headset’s device information from the Bluetooth device and then pair them again.