Initializing the headset to restore factory settings
Remove the headset from the charging case to turn off the headset by pressing and holding the button on the left unit for more than 2 seconds, then press and hold both the button on the right unit and the button on the left unit for more than 15 seconds.
The indicator (red) goes into the flashing state then the indicator (blue) flashes 4 times ( ), and the headset is reset to the factory settings. All pairing information is deleted. In this case, delete the pairing information for the headset on the device which has been connected, then pair the headset with the device again.
If the headset does not operate correctly even after initializing, consult your nearest Sony dealer.