NOTE: Both the Belkin AUC004 earbuds must be charged to perform a factory restore.
How to perform a factory restore
Remove the earbuds from the case.

Step 2:
Place the earbuds back into the case.

Press both earbuds for 6 seconds.

The indicator lights on the earbuds will alternate blue and white.
Step 5:
Close the lid. The earbuds will now be back to factory defaults.