I know, I dont. Must be something firmware and battery unrelated as I had this like 2 years ago with a cheap not unupdatable device too and a VTC mini, something that different devices with different boards must have in common, id think. And it came when the mods got older. I really had my hopes up when someone mentioned that it may be even the inner threads of the pico battery cap, but sanding and cleaning all those conducting parts didnt help.