Update to latest infomir firmware is another option, if not try below.
Also could try pressing the button left hand button on mag remote, looks like a rectangle with arrows on each side.
This can toggle screen fit sizes/zoom/stretch etc.
Also may be worth trying a different HDMI cable / port on TV, aswell as rechecking display settings/redo etc
Check you display settings and display reso.
Also aspect ratio when on stream.
Because you monitor offers higher resolution and higher aspect ratio than the movie/TV program is produced in. The way it is showed is the way its meant to be shown to get a clean non distorted/non warped image. Hardware these days are ahead of the movie industry standard right now.
EDIT: I think I found the problem, I did an update and it seemed to fix the problem. I will do the update on the other boxes tomorrow.