Sounds like a very likely theory. You can see if cleaning up the center and edge contacts helps. There can be quite a bit of gunk that builds up where the plug inserts into it. May need some fine grit sandpaper to clean the buildup off. If this is the kind with a spring plunger to lock it on, the grippers that open/close to grab onto the side of the plug sometimes bend outward a bit, making the grip less dependable. Careful work bending them back in a little with a needle nose can temporarily make the connections tighter. But the metal does fatigue, so it will loosen after a while again. Something to try while you wait for Amazon to send a new one! My Dynamite's have seen many years of service, and still going strong. McDaniel has been around for a long, long time but the cell is not easily replaceable, and the brass versions are a lot less long lived than the stainless ones. I'd avoid most others, especially Chinese clones.