I had the same problem until I found out the flex cable for volume and on/off buttons was slightly torn. In the process of replacing it and removing old cable, the camera connector came off motherboard. I was hoping it would not affect on/off or volume but I guess it does, because after put new cable in, volume or power button still does not work. I don't care if the camera does not work, but now I am ready to give up on using volume and on/off button.