One of my tv's is blank with a little square in the center that has a blue border and a circle in the middle, after unplugging the hd cable box the screen came back with a no signal message. Not sure what to try next?
This problem sounds like it may be HDCP related. Try removing the HDMI cable from BOTH ends and re-seating.
If that does not resolve, do the same but also, remove the power to the box and TV if you can.
Let us know if that resolves it here.
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