I have (3) (Models STC I450, STC I550 and 650IR) Stealth Cams that have worked well for several yrs. I have ran these successfully using external 12v battery packs. Recently, I started having problems with them working with the packs, seems that they will only work with internal alkaline batteries which they burn thru quite rapidly. They should work with the external batteries without the internal ones, but they don't. Has anyone else had this problem and if so, what is the fix, if any?? According to Stealth Cam customer service, the cameras should work if I have 12v supply available. When I checked the battery packs, they read around 12.75v and appear to be fully charged, yet the cameras will not operate. StealthCam will replace them for a fee........? Any suggestions would be appreciated.