Tom, I couple of questions in response to your problem. Are you tuning the piano to standard, or leveling it off at 438? When you say that the all the notes were being lowered starting with about -1.38c, are you talking about starting with A0? Which pitch raise (lowering) mode did you use; +3%, standard, -3%, etc. If you are tuning to standard your problem doesn't make as much sense unless you have experimented/changed the octave stretch setting. If you are used to, say, tuning to the RPT setting, and went to a wider octave stretch, then you would be lowering notes almost into the temperament area. In the higher treble areas you would see just the inverse. -1.38c is not a lot of lowering on a note. It's possible with it being summer and all -high humidity in some areas, that some notes have gone slightly sharp. Remember that the note that you are tuning is it's cents deviation, averaged with the 6 notes before it. This is done to assure smooth transitions being intervals.
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