Hi haarvik, you sure seem like you have a stumper.
The only other thing I can think of is that maybe stress is helping you hold on to your pounds? (if you're not stressed, you don't need to keep reading
However, stress releases cortisol, a hormone that affects weight. It can make you gain or make you maintain even when trying to lose. Even worrying about why you're not losing might be enough to trigger it.
How about adding some yoga to your routine?
Just brainstorming...not intending to get into your personal stress level here...
Looking forward to the post when you tell us you've broken through; good luck!