I've had this phone for 3 days and only charged it once from its initial 50% charge to full capacity. Now it's down to 28 and won't take a charge from a wall socket or the USB port. It also doesn't recognize when the USB port is connected to the PC. I did a hard reboot and downloaded the latest USB drivers from Samsung, to no effect. Compared to my old phone, the micro USB port does feel looser with some wiggle room, but I've played with it extensively without getting either battery or USB connection. Ideas?