I agree that the LED backlight is the best guess. It could be the drivers for that strip but never has it been anything that avoids disassembly and testing. If you don't do this sort of work, then get estimates.
Hi all!
So I’ve had this tv for about 3 years and noticed that the center and top half of the tv has been darker than the bottom. I have seen posts similar to this saying it’s the backlight strip? If anyone has other advice on what it could be I would appreciate it!

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