Welcome to Android Central! Randomly? You mean sometimes you don't see ghost images? Burn-in means the ghost image can be seen all the time (depending on the background color), so it shouldn't be random. If it isn't true burn-in, I'd wonder about either a software problem or a hardware defect. If it persists in Safe Mode, after a reboot, or after a factory reset, then I'd bring it back to the store for an exchange, or contact Samsung for warranty repair or replacement.