Only one earphone is emitting sound instead of both

It is possible that your headphones have not been paired correctly and that is why only one is emtting sound. To fix this, follow these steps:

Important: make sure that the coloured strips that cover the charging contacts of each ear piece are removed and that the batteries have been charging for a while.

1. On your mobile: remove previous links Settings- Bluetooth - (delete, forget ...)
2. On your mobile: turn off Bluetooth.
3. Take out the headphones and press the touch pad five times in a row. You will hear a "du". That means the reset worked.
4. They should start blinking for a few seconds and then one will stop blinking, that means they have been paired.

Now they can be linked to the telephone.

5. On your mobile: turn on the Bluetooth.

6. Go to Settings-> Bluetooth, search for the earphones to connect.