Reply to Midifighter + Reloop digital jockey = unresponsiveness

Hi

I have downloaded the new traktor pro 2 mapping (found here) for my reloop digital jockey 2.
The mapping works fine on itself but when I use the digital jockey together with my midifighter (link here) the digital jockey becomes unresponsive after a while of usage. Meaning it does not react when I use the buttons or jogwheels,... . The midifighter still works like a charm.
The only thing that resolves the issue, is disconnecting the digital jockey and restart traktor pro 2.

When I use the traktor pro 3.4 mapping (found here), everything works just fine.

Did/Does someone have the same issue and solved it?

Configuration:
Mac OS X 10.6.8
Traktor Pro 2.1.2