Analog Lab : keyboard split is faulty

[batman37]

Hello,

I  want to split my Arturia Keyboard (Analog Lab 49) :
A lower part (midi channel #2), and an upper port (midi channel #3). Kontakt Player 5  is running on the computer (Win 7 64 bits) with 2 VSTi (channels 2 and 3).

Transpose is set to 0.
I set the split point to C4 (setup->global). When playing, the frontier between the instruments is on D4#, not C.

Thanks for your help