1.Faulty HDMI cable
Used the one supplied with the box and a second cable with the replacement box, still flickers.
2.HDMI connections not secured correctly
3. Faulty HDMI input on the TV
Moved inputs and still flickers, no other input device behaves like this including the SkyQ box this virgin TV replaced.
4. Tried a different TV to replicate the problem?
It doesn't flicker on the bedroom TV as tested when we switched the boxes round.
5. HDMI cable not to specification?
I bought a certified 4k cable to test this and the problem is still there.
Is an annoying flicker whereby news presenters clothes appear to pulse or the green scenery in the background is fading up and down in a strobe effect. The screen or picture don't actually disappear then reappear