We'll mines doing the same thing kind of. On battery power I noticed that once it hits 40% battery you search the web or emails or even to some texting it will lock up or freeze and then let it set and it reboots on its own. Then it will lock up upon restarting and do it again about 3 times in a row. Did a factory reset yesterday and today sane thing. So since it off warranty I eaither deal with it or do an insurance claim.