Problems with calibrating MMP

Got my MMP (running the original V1.22 software that it came with).


When I tried to calibrate it (turning the switch on while holding full throttle etc...) it registered forward fine but it didn't register brake/reverse ( and of course I didn't get to the neutral calibration part).

I'm running 2 MMs and one MMM in other cars with the same radio gear (Spektrum DX3R) and never had problems calibrating.

I tried to reverse the throttle channel and different throttle/brake end points but it didn't help.

Any ideas how to calibrate?

BTW - I tried running the car without calibrating the MMP and everything seems to be acting normally, the MMP isn't dead or anything, just won't calibrate.