STEP 1: Unzip the file "PXN-9607X Firmware Update-V1.26" or above, then click "9607X V1.26 Firmware.exe".
STEP 2: Press and hold “L3” button on the left joystick of the controller until the controller is connected to the PC via the USB cable, then click "Update Firmware".
Note: If the upgrade works, a prompt "Upgrade success!" will pop up, then you can pull out the controller.
Note: Pressing down the left joystick of the controller will trigger the ”L3” button
Download the "PXN-9607X Firmware Update-V1.26": https://www.e-pxn.com/sites/pxn/files/tools/9607x-v1.26_2.zip