Hello @Klaus-Wittstock,
as stated in the readme file in the Firmware which is distributed in the image gets automatically updated at first boot? Did you wait a few minutes to let it flash correctly? If yes, there was some issue with FW for the analog boards, that caused such issue,s, but that should have been taken down.
Anyway from what it seems, the FW on the group2 is damaged and currently the only way to fix it is to send it back to us... Please send me an email so we can discuss it in private.