Nvidia Shield - Flickering Issue

**Background** I have an Nvidia Shield connected to my TV and have used it for many months successfully. This morning when I turned it on, the screen was flickering: it will change to showing the home screen for about 1 second then either a black screen or the "snow" screen for about 4 seconds, repeating. I have not changed anything recently like cables, tv, or any hardware. **What I have tried** I did look online and most posts regarding this are 8 years old or so and suggest trying a new HDMI cable, unplugging and plugging in a bunch of times, or that the resolution is getting off. I did try a new cable and different tv but same issue. When I boot it into safe mode the flickering goes away. If I try to change to any of the available refresh rates, it works fine in safe mode still but same behavior once I restart out of safe mode again. I even tried a full factory reset and still have the same behavior. **Question** I am open to any suggestions for those who have had this issue before. My question is how do I fix the flickering behavior? More than likely it is a resolution issue, and maybe it is linked to some sort of recent firmware upgrade? I was not notified that there was one any time recently though.