I had the same problem, and when speaking with Alesis they authorized a RMA. However, I never sent it back. I got it to work 'fine' by having it fail the calibration on closed hh. However, since the latest update, I didn't have to do that anymore.
Now, I say 'fine' because I have nothing to reference it to, except an accoustic. It doesn't perform that well, but I've gotten used to it.
The latest update ("i", I believe) added settings to hh tweakability which works pretty good.
Hope that somewhat helps.