I would try flashing your shipped ROM
let it get totally all set up then pullthe battery for 5 min.
Then hard restart again. shipped ROM found here-->
http://rapidshare.com/files/17615341...3_Ship.exe.zip
Then I would flash to a super stable ROM like MightyROM4, found here-->
http://www.lilrico.com/Mighty/ROMs/M....09_Herman.exe
Then pull the battery for 5 min.
Then hard restart again.
I know it sounds like a bit of overkill but if you do all this just as I said and your still having problems then chances are its a hardware issue .