I HAVE HAD THIS PROBLEM ALSO. My Tab is 2 years old, but worked great up until a week ago. I baby my tab, never been dropped, or even touched by another person. Has always been in a Otterbox since purchase and used maybe a couple hours a week. I have a virus scan since purchase. I have also recently it I guess what is like wiped out so it was like before I purchased with a Samsung tech. and still the screen blacks in and out. Very frustrating, please help!