...referring to for changing channels? If so, don't forget that rogue radio waves can cause all sorts of troubles. It's likely you are encountering just such a scenario where the extra telly is located.
What happens when you move the 3rd TV w/ Magic Eye to another location in the home?
Did you try using the anti-interference device listed on the following site:
http://www.aerialsat.com/search/tag/sky-magic-eye.html
I have an analogue flat sceen LCD TV which has started to be affected by interference. This is a 3rd TV in the house and uses a Magic Eye to watch SKY TV. All other TV's in house are perfect and not afected by any interference.
Horizontal lines, clicking, crackling, then screen turns black, volume reduces. This usually lasts a few seconds then returns to normal. This is sporadic, not regular. It can happen every few minutes or sometimes stays clear for hours. When good the picture is about 98% good.
I have tried swopping with a spare Freeview incorporated digital TV but it does the same. (wouldnt tune to many channels though). I have also tried an in-line 4G filter but that stopped reception alltogether.
Any suggestions mucho appreciated.

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