Hello, I just unboxed a New Onda Vi40 Ultimate that I bought from Androidinabox. I let it charge for a few hours. When I try to use it, it reboots mostly when I try to unlock the screen. If I get past that screen, it will randomly reboot every minute or so. Is this a defective tablet? I have to say, upon unboxing, this tablet looked used. The clear sticker on the back of the tablet is so scuffed up from usage it looks like it's been used for a while. Also, the box tabs inside were used prior. It defiantly looks like it's been reboxed. Very disappointed in this purchase. Any help would be appreciated to rectify the rebooting problem.