EAS Code

Every night the box in my bedroom displays 'EAS' which I assume means emergency alert system. When I turn the TV on, the image is black and no sound. Doesn't matter what channel is selected. I can cycle through the cox activity menu and that is about it. If I run a diagnostic all signals are receiving properly. I have power cycled the box already and still get the same issue. Again, this only happens at night, probably sometime after 7p and lasts into early morning. I am at a loss..