I don't own one of these, so have never had it apart, but from what I can infer about the construction it has small momentary tactile switches beneath a hard plastic sheet. If you were able to find the equivalent switch (Digikey, Mouser, Newark, etc.) and were good at soldering you may be able to repair it. Otherwise, I don't know. Maybe give it to me? (Just joking unless you really want to) ;-)
Jim