Hi Jesper,
I remember that there was something to do before having some midi responding on the 9 but I don't remember what. Therefore I took the manual to see the answer back then. It was weird with some Midi modes to assign like Two TX1 or something like that.
Thing is last time I tried I couldn't get it working anymore neither for some reason.
I suppose you have seen and tried that Midi mode stuff?..
Maybe you gonna have to dig in the schematics of the Midi part.
Patrice.