I've come to the conclusion that it's the instrument used for the melody that bugs me.
Anyways, nice and clean mix the lower bass notes are especially good, it has a little too much mid frequencies on the highest notes.
I made a remix fast because I wanted to hear how the melody sounded with a different instrument http://tindeck.com/listen/ckpw
I'm sorry, I feel like I shouldn't have commented in the first place.