Why after a downgrade of the firmware from 1.20.nn (or later), to the FW 1.18.nn (or earlier) the VGA or SVGA Panel does no more start up and the buzzer does squeeze regularly?

FAQ #101826

 

This could happen because the FW 1.20.nn does reformat the filesystem on the panel in a new way and the FW 1.18.nn does not know this new filesystem format.

To solve the problem, the filesystem of the panel has to be re-formated.
This can be done in the following way:

1. Power off the panel
2. Push a screwdriver in to the 3 mm hole where the reset button is located.
    - for the 5.7” panel is on top of the panel
    - for the 10.4" and 12.1” panel it's near to the USB connector.
3. Press with the screwdriver on the reset button.
4. Power on the panel and keep the reset button pressed until the buzzer reaches
    its high pitch frequency and comes back to its base frequency, then you can release the reset button.
5. Wait about one minute until the panel reboot itself.
    If it takes more than 3 minutes, then reboot the panel or repeat the whole procedure.