Occasoinaly my phone likes to reset it's self, It could be in the middle of a phone call, while idle or anytime it pleases...I'm believing that the SD card could be corrupted and causing the phone to crash cause it only happens while running a program on SD... when the phone has it's "episode" the phone locks up, the screen goes black, the 4 (haptic buttons) menu,home,back,search light up and than the phone's screen lights up on the lock screen, and in the notification bar the "media scanner" is running... if you are confused with what I posted or need any more info from me let me know thanks..