When I turn on my projector, he does the same. I have a 10 meter HDMI cable connected to my projector and the image is not alternating.
On the contrary, we even feel that it is better (may be due to the output amplifier of this little box).
In any case for me it is a great product.
Only flat, facade color leds enough "Flashi". Put it in a hidden corner or behind your TV stand and voila.