I find although most alkalines have a shelf life of years, after you use them (draw power off of them) just a little, you start a chemical reaction that may cause the battery to leak in a few months. So after you start using alkalines, you have to use them up in a couple months or throw them out, or they'll leak. Also alkalines that have exceeded their shelf life may leak. The slightest leak can cause your equipment to fail. It may not look like much, but clean it all out.
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