ah, thats my damn orange brightbox router to blame there.
I cant access my site using the normal address on my network (the brightbox is crap and doesn't support loopback), so i have to access my site using the internal IP addresses, so that failed to tell me that the dyndns system was updating, damn brightbox.
Cant believe such a modern router fails to have a simple feature that surely is needed more and more often!
Because of the box, i cant use the app on my wifi network. I will have to get it replaced.
Thanks for the help though!