I've got a MH12GTS and it will not charge past 3v using the usb cable. If I charge the battery with an external charger it will fully charge to 4.2v. I've tried other 18650 cells in the light with the same results. Anyone else have this issue with any of the other nitecore lights? I've emailed Nitecore a few days ago but haven't recieved a response yet.