I noticed my crystal whined a bit, even not long after roughing up the surface. Then I looked at the end of the striker and noticed it was shiny and roughed it up a little to take of the shine (make it not so smooth). It seems to grab much better now, and the sound is fine. Do any of you do this? I don't want to mess it up, but figured if the striker is too smooth, it won't grab as well and makes the call whine....