There is a black box in the lower right on the screen that says, "A new software update is available. Would you like to update now?" Choices are Show Details, Update Now, or Update Later. Update Now is highlighted, but it won't actually let me select anything on this menu. Roku is fully operational behind this stupid overlay box that will not go away. I tried to power TV off and on. I've tried going to Settings and updating manually, which worked successfully, but the box is still there. It seems to be part of the black background since I can barely see the picture behind the box.
Kudos to you for bringing this problem up. I have the same problem. I hope ROKU is preparing a FIX for this problem. I can't see the picture because of the "New software update is available" that won't go away.
Please let us know what you are doing to correct this problem.