Sony MDR-MV1 Open-Back Reference Monitor Headphones - Manual (Page 120)

Help Guide
Wireless Noise Canceling Gaming Headset/Wireless Gaming Headset
INZONE H9/INZONE H7
Initializing the headset to restore factory settings
If the headset does not operate correctly even after resetting, initialize the headset.
Turn off the headset.
Remove the USB Type-C cable.
1
Press and hold the (power) button and (Bluetooth) button for about 10 seconds or more.
INZONE H9:
When initializing is complete, the left and right ring indicators (white) flashes 4 times.
INZONE H7:
2
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