Jens,
Yesterday I tried to recreate the issue again from cold on the 24th Aug firmware before flashing the Sept firmware, just to get a pre-flash check. For some reason the issue wasn't occurring which I thought was annoying from a consistency point of view. Anyway I launched the IndivisionAGAMK3 app and on a few occasions the app failed to recognise the presence of the card, even though I was getting a picture and appeared to be working - just not recognised, even when starting up without startup-sequence. Eventually it was recognised.
Continued to test with the Enigma (my test demo) and still it didn't produce the issues I've seen previously. Anyway decided to reset the MK3 back to defaults then flash with Sept. firmware as a test. Result was the same, no change - the demo was working fine. Also noticed large white blocks flashes in workbench while moving through the menus or dragging windows around, but only when running in colour modes above 32, i.e. 256 colours (standard PAL mode). I wasn't getting this when I first had the MK3. I didn't see any such flashing via the RGB port connected to my Philips CM8833-II.
Today I decided to flash back to Aug firmware and test the demo once more from cold. This flashing process was successful, the firmware version was showing as 20200824 from the Live Edit mode. Running Enigma again I did see the flicking issues for Enigma demo as I've done over the last few weeks, so I thought great, I'll flash immediately to Sept firmware and test again to see if the new firmware has fixed this.
I launched the IndivisionAGAMK3 app and selected the Sept firmware, and.... no screen. Via the RGB port I see IndivisionAGAMK3 app had crashed during the flashing procedure! Unable to continue I soft rebooted, launched IndivisionAGAMK3 and it reports the MK3 is not detected. If I click continue, it crashes with error #80000005
Multiple power cycles of increasingly longer periods yields no change, the IndivisionAGAMK3 app does not recognise the MK3 and there is no picture via the card. RGB is fine.
I'm using KS 3.1.4 and have an ACA1233n-new 26MHz installed.
Using v1.5 of the IndivisionAGAMK3 app
What next please?