At first glance, nothing is noticeable, have you taken a closer look at the buds? Put on some gloves and gently break apart the bud with your fingers to check if there's any mold, preferably down to the stem.
Most of the time, you only notice it when it's too late, but the buds change color and dry out, becoming more brown/yellowish/gray.
Try not to exceed 60% RH and ensure plenty of air circulation to prevent mold.