Since the Saphe Drive screen uses a different technology than the one you find in various phones, televisions, computer screens and more. This means that it does not emit light, but simply colors some small cells black, which means that it uses less power than other technologies, as an image can be shown without the device constantly having to refresh the screen. Instead, it risks freezing the image, so to avoid blurring on the screen from previous images, your Saphe Drive traffic alarm refreshes the screen approx. every 500 times that the image is updated. This means that it removes the color from all cells completely for a few seconds (it becomes completely blank). Subsequently, it again displays images on the screen.
So it is not a defect, but a safety measure that allows you to have a traffic alarm that is easily visible and that does not need very much power, and therefore can hold power for a very long time.