I cannot get this unit in pre-boot mode.

What happens is the following:

  1. I power on the unit.
  2. I put one finger on the G-A, another one above.
  3. The unit blinks the word “system” a few times.
  4. Next, the unit displays the word “loading…” a few seconds.
  5. Finally, the unit starts, but in the normal way.


Can anyone tell me what I’m doing wrong?

Thanks for any help !