I wonder if it's our old friend corrosion. It's not user serviceable if it's that but I see a friendly TV tech made a video of one possible cause. Remember this is not user serviceable, there are lethal voltages inside and dogs are sleeping with cats. The effect can be in an area or full screen.
-> https://www.youtube.com/watch?v=WuwG5wqxTpE
Hi Guys,
First of all, thanks for letting me join this group.
I have an older model TV and am experiencing contrast and brightness issues. It's on Home Mode but, regardless of the Contrast, Brightness or Mode settings I am getting coloured "floaters" (for want of a better term) on the screen. An example is a blue moving band on a sky or other ones depending on the background colour of the picture. Does this mean that the screen needs replacing or could it be that a component is failing? It happens regardless of whether it's on HDMI or Scart input. I hope this makes sense!

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