Take it back for the reasons stated and start over. If the seller balks, call it defective on arrival and get a good one.
I have only recently ( last 2 weeks ) bought this tv. Its been on hold for me - trying to save for it. Was boxed. all items within - so i am hoping its not ex display.
But when i switch on or flick between the sources - the right side - mid way up - white beam about 3 inches wide from edging to fade in mid screen.
Noticeable on dark back grounds - and during watching of programs this flickers , like a strobing effect.
Did not expect this on a new tv
your thoughts would be appreciated

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