Wim, I've had similar problems with a restrung B. I suspect part of the problem is due to the high volume of air flowing around the piano from the air handler fan speed. Fresh air from outside is required to keep air healthy. My situation worsened after the building had fans upgraded and outside dampers improved to bring in MORE fresh air. Another possible cause is loose bridge pins caused by the extremely dry air in commercial buildings in the winter. I'm planning on doing an experiment with epoxy in bridge pins in one section to see if things improve. Good luck! This can be extremely frustrating! One of my secret fears is that people will think I don't tune the piano at all, *OR* that I do a lousy job!! : ( John Minor University of Illinois I
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