In the original message, the puzzle stated that the click was present when A#4, B4, and C4 were played. I think it's odd that the upstop rail was warped in a way that caused clicks on three keys that were not even adjacent to one another. (two adjacent and one nearly an octave below) Correct me if I'm wrong, but those are not adjacent keys. A#4, B4, and C5 would be adjacent. Tom S.
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