Anyone here using Amplitube 3 with an expression pedal to control wah?

My problem is that no matter what wah pedal from A3 I use, I get a very narrow range where my pedal goes from all the way down to all the way up, so It's very hard to control, I have maybe around 1 cm range in the middle on my expression pedal where all the range of the wah sound is.

Im using a Roland EV-5, I've tried adjusting the pot on it but no dice.

Wrong pedal for the job maybe? Any suggestions?

I've tried some of the software and autowah's and never got the full effect I wanted.  A friend found a Dunlop wah pedal at a garage sale recently and gave it to me.  It needed cleaning up but it works and the "real thing" works best.