The first thing that I am suspicious of is the capacity in your humidor being used. If you have enough room in it to put a shot glass with distilled water, one of your problems may be that you have too much air and not enough cigars in the humidor. I know it sounds crazy but I found this to be true: The fuller your humidor is, the less variance you will find in RH. It is most difficult over the winter months because as we all know, the cold knocks the humidity out of the air. Every wintertime I make sure to fill my humidor to capacity (this is not a joke) and I do it expressly to protect my cigars from drying out and to keep the humidity from bouncing around. A fuller humidor and a watchful eye on the hygrometer pay off in the winter time, also, this is definitely the time to be decisive when opening the humi, either you are in there for a) recharging of beads/other humidity device b) you are throwing some sticks in there or c) you are getting a cigar out you want to smoke. Not wasting time with the lid open in the winter time and exchanging out all of the air is pretty important during the colder months. It would make your life easier as well if you could find a place where you can maintain a constant temperature conducive to storing cigars in the winter months, but filling your humidor up with leaf will help out greatly.
