If no sound can be heard from a single earphone, perform the following steps:

1. Go to Settings > Bluetooth on your phone or tablet to check the earphone connection status. If the connection fails, troubleshoot the issue by referring to Unable to pair HUAWEI earphones.
2. Update the earphones' firmware to the latest version by referring to the earphones update guide.
    

   • For the FreeBuds 4/FreeBuds 4i, if no sound is heard from the second earphone taken out of the charging case, place both earphones into the charging case and update the earphones' firmware to the latest version to fix the issue.
3. Update the phone/tablet to the latest HarmonyOS version.
   

   If this issue occurs when pairing FreeBuds Lipstick/FreeBuds 4/FreeBuds Studio/FreeBuds Pro for the first time and you follow the onscreen instructions to pair the earphones with your phone, take off the two earphones and put them on again, or update your phone/tablet to the latest HarmonyOS version.

4. Take out both earphones and place each into the charging case to see if the indicator turns on. If the indicator does not turn on, it indicates that the charging contacts are in poor contact. In this case, clean the contacts and put the earphones back into the case. Skip this step if you are using the WATCH Buds earphones.

   

5. Take out both earphones and place them into the charging case, and close the cover. After 5 seconds, open the charging case, take out the earphones, and try again.
6. Restore the earphones to their factory settings and pair them with your phone/tablet again.

If the issue persists, take your device and proof of purchase to an authorised Huawei Customer Service Centre for assistance.