I have transferred most of my tobacco from their tins into Mason jars for longterm storage. I think you call them Ball or Bell jars in the U.S. Maybe those are just brand names, but you guys know what I mean. Anyway, most of the blends I've been smoking from the jars lately have obviously suffered significant moisture loss, IMO. I like my 'baccy more on the moist end of the spectrum, that way I can dry it to my specifications. I checked all the lids and they were tight and free of bits of tobacco that might compromise a tight seal. None of the jars are older than June 2012, as that is when I started smoking and cellaring. Is this a common occurance or do I need to switch brands?