Mik,
Just a thought here, maybe you should change out your ten and try ten more, just because there is thousands of Batts out there im sure that youve sold. All battery manufactures that make batteries could make 500,000 Batts and there would be some problems with some of them, and it does happen, No different than a car battery, it could last 12 months and then a problem and you could get one that last 6 yrs with no problem. Bottom line im just trying to make a point that maybe if you got one of these having the issues, you might better the Battery in some way. I had some of these problems these people are speaking of, I also sent mine in and it turned out to be my charger, so maybe thats a problem and im thinking it might be. Janty Rocks with some of the best customer service out there, Ethan Hats off to you brother.!!!