Yamaha DTXpress/DTXplorer/DTXtreme

I can't seem to get the "middle" sound out of my hihat pedal and 
controller.  I can only get the 'closed' and 'wide open' sounds, and 
can only occasionally get the 'slightly open' hihat sound (if I 
press the pedal just right).

Is there a way to configure this to make it easy and consistent to 
get all three hihat position sounds?

Thanks!

Mike