Seem like i just got a dud camera in the door from Amazon. I unpacked it, put in a SD card and then put it on the charger ( use a old 1.3 A phone charger ) After a hour i turned it on to look at what firmware was on it ( 1.2.4 as i recall so needed to go DL new firmware ) So now + 2 hours later i want to format the memory card in the camera while still on charger, but now the camera can not turn on at all. During charging the red low voltage warning LED was on but it have now turned off, so i tried to measure voltage on the battery and it is 4.2 volts so it should be charged. But still nothing i can do with the camera now, when i put it on the charger the red LED come on but shut off after a few minutes, but that's also the only sign of life in my SJ8 pro. Just with battery the camera do nothing, removing battery and putting it back in don't help at all Looking at little manual in box or online manual from SJcam site give me no alternatives to try, i have also tried with no memory card, and with 2 other U3 cards.