@sdetweil The 3 error entries in the log file only appear at the point in time that the xrandr off is issued. They don’t appear again until the screen has been turned on again and another xrandr -off gets issued.

I tried this, but same problem with sample config. SD-Card is in there fro the beginning, at max one year… Will try a new one, but have to get one first ;-) Maybe this is the solution. Thanks, I will come back to you. If it’s not the SD I will try to connect the keyboard and check the DEV Console for errors.