Coincidentally last night I noticed a strange pattern in the upper right of my screen on red backgrounds.
Turns out it is screen burn from the bright red stylised logo just before the word FreeviewPlay on the TV Guide page.
Now I do use the TV Guide daily but obviously I don't have it on screen for more than a minute at most and I always run the screen on ISF Expert Dark.
Looking through test patterns Red, Green, Blue, Yellow, Cyan, Magenta and Grey the only issue I see is this FreeViewPlay logo.
Attached a Pic, it's about 5" to the right of Joe Lycett's hair.
how did you run the test patterns? Is it external software?