After every reboot of my HM4.1 the date and time are reset to March 12th, 5:55pm. Only a browser sync solves this, enabling of disabling NTP servers doesn't seem to do anything.
Does anyone recognizes this or know how to solve this?
The problem was that my HM could not connect to the internet. I added a custom DNS-server, and now it works fine. After every reboot the date & time are correct and synchronised.