I'll bet one of your Kawai experts can help me with a myster buzz around C6. Well, it is ON C6, but also a few notes above and a few notes below. To me, is sounds like a buzz from a crack but it might be described as a kazoo sound.... Check to see that the stretcher is secure. Sometimes a tiny gap exists here between the stretcher and the pinblock. Push hard on it and see if the buzz goes bye-bye. Also, look at the lock, if it has one.
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