I had kept a few brushes inside of their boxes in my bedroom closet for storage. I took some out to revisit them and noticed a bunch of hairs were falling out. These brushes were put away perfectly dry. One brush was a cheap Stirling was shedding hairs like crazy- that one was just wrapped in tissue paper with no box. The box was kept on carpet in a dark closet for a few months. I wonder if there is some really hard to see carpet bug that is destroying the hairs? I had 2 brushes in a well sealed tube and they were perfect. It would seem something is eating the hair but I cannot see what it is with my eyes.