When both the earbuds and the charging case have no battery left, you first need to charge the charging case alone to a certain level in order to prevent Sudio Nio from rebooting in a loop. If the earphones are rebooting in a loop, they will not longer function properly.
To charge the earphones correctly, please follow the steps below.
- Remove the earbuds from the charging case.
- Plug the charging cable into the charging case, and let it charge for at least 15 minutes.
- Put the earphones back in the charging case, and let them charge.