How to reset or initialize the Wireless Headphones (WH-1000XM4)
Reset the Headphones
Step 1
Plug the USB cable into the headset to charge.
Step 2
Press the POWER Button and the CUSTOM button at the same time while the USB cable is still connected.
Step 3
The headset will reset. To charge the headset after resetting, disconnect and reconnect the USB Type-C cable.
Initialise the Headphones to Factory Settings
Step 1
Turn off the headset, and ensure no USB cable is connected.
Step 2
Press and hold the POWER button and the CUSTOM button for 7 seconds or more. A blue indicator light will flash four times.
Step 3
The headset will initialise, resetting the settings and pairing information.
Step 4
Delete the headset from the list of Bluetooth products on your device.
Step 5
Pair the headset to your selected device again