If you try to flash a firmware version older than the one currently on your headset, the bootloader will reject it. At best, you get an error message. At worst, you brick your device (turn it into a non-functional paperweight).
Ensure your Pico 4 headset has at least 60% battery life to prevent shutdowns during installation. pico 4 firmware downgrade free
Search for authorized community archives (e.g., OwoMushi Pico Firmware site ) to download the target version. If you try to flash a firmware version