I have contacted the support, but maybe someone ran into this.
After a couple of seconds - up to minute, al buttons/switches turn off, they don't work, only way to turn off the Kemper is to pull the cord. Display is still lit, but no text at all. Running latest firmware. Sound is ok I can still change rigs via rig manager. After forced power down everything is ok for a bit, then off again.
Pics attached.