No VGA signal from RGB DUAL board.

[gelo29]

Hello everyone,
I have problem with my new RGB DUAL system:

• there is no signal on my VGA CRT monitor (Samsung SyncMaster 957p).
  I've installed the newest version of RecalBox (9.2.3-Pulstar) on micro SD card and put it into my RSPi 5 with RGB Dual installed.
  Of course, before this I've also set the proper refresh rate (31 kHz) on RGB Dual board micro switch.
  Now, when I power on the unit, nothing appers on my screen monitor, there is no signal.
  Do i do anything wrong?
  As far as I know it should be plug and play, no additional settings required, right?
  Thanks a lot,
  Greg