Is he scratching a lot? Do you have anything wooden in his cage? Is he losing quills? How often do you bathe him?
He doesn't scratch a lot, just every now and then but I do hear it a few times at night. No quill loss at all; I never see any quills on his liner. The only wooden thing in his cage is his tp roll. As for baths I don't use soap very often. I've only done that two or three times in his life. I only give him small foot baths with about two inches of water in the sink.
My mom told me that if it is due to bathing, then there is something in the water. We have a well, so its not as good as city water.