Definitely need more dehumidification, especially if the air conditioning goes off periodically. A/C tends to lower humidity, so rather than going thru a pitch lowering, wait until the A/C comes back, and see where you are then. In general, you would probably want at least two or three rods, strategically placed parallel to the bridge, and elsewhere. Check with Dampp-Chaser for their recommendations. There might be an argument for more humidification as well. regards Steve Pearson, Yamaha service
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