If the problem is unique to that piano then it probably is not your method. I would begin to wonder about the player, or maybe someone is generously spraying a bad cleaner on the keys, or maybe has habit of spilling coffee which dries and hardens the felt. Annual bushing is not so out of line for the heaviest use pianos with top priority, but even in those cases I'm doing good to get it done every 2 years. Dennis Johnson St. Olaf College
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