I tried some more things and changed one setting that I have done to overcome issues with nvidia hw transcoding.
in grub I changed the following kernel parameter:
GRUB_CMDLINE_LINUX_DEFAULT="text acpi_osi=! \"acpi_osi=Windows 2015\" mem_sleep_default=deep pcie_aspm=off"
As far as I understand is, that this is telling Linux it is on a windows system.
After I changed it back to:
Everything seems to work. Autoshutdown service is active and HW transcoding is operative.....
Does this make sense to you ?