I just got the Mobile Keys 25. I have a standard expression pedal, a Behringer FCV100, which I have used with other USB/MIDI devices without incident. However, when I hook it up to my new keyboard, and run it through FL Studio, rather than detecting a continuous input, it is treated like an on/off switch. I get no control change until I am at near 100% where the software registers full value, then if I move back at all, it goes to zero. I have tried remapping the control to something else in case the software was making the mistake of thinking it was a sustain pedal or something. I'm definitely in the right jack, and the pedal is set up correctly. I have tried it both with and without AC power, and with different cables. Same result. What's going on here?