I got a new wall charger recently after giving my original one to my mom. The first night, I plugged it in and screwed in a batt I knew needed charging. Light stayed green, battery didn't blink or anything. I unscrewed it and screwed it back in and still nothing. I put the batt on the usb charger and it worked.
I then tried one of my XL batts in the wall charger and it worked perfectly. Have no idea what would have caused this and no idea if it would still happen, I forgot which batt it was as Ive been mainly only using my XLs, but I'll do some testing tonight to see if it is still acting up.