midi signals interpreted strange by tractor

hey there. i have a little confusing problem with my self built midi patch for ni traktor. the patch simply converts the incoming signal from my monome into midi data. in one case either traktor or max/msp does something weird. i've created some list up/down buttons to browse through my library. its just a simple chain of an if and an append object. if i press the button on the monome the list in tractor is jumping 2 rows forward - it's meant to go only one forward. i've checked everything so i didn't find any clue that the midi signal is sent twice to traktor. if i simply type the midi command into a message box and send it out by clicking on it traktor behaves like it should.

has anyone else expierienced strange behavior like that and found a way to get it fixed? the problem turned out since i've switched to lion...