You should be able to fix this by going into the Video Output settings in the V6 box's settings and disabling the 2160p settings and make sure that only 1080p and 1080p passthrough are enabled. This should then allow it to play.
Another fix for this is to change the HDMI ports one by one in the back of the TV for the V6 and keep trying to play the Movie until it works.
The first solution I've suggested should work first time though.
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