Take it up as a warranty issue or if new, return for a good one.
I have recently purchased a Samsung 32" LED TV, model UN32M5300AFXZA.
When the screen is white or has brighter images on it (such as images of a clear sky or white walls), there are eighteen spots that appear brighter than the rest of the screen. When the images move it appears that there are smudges in these places on the tv screen. I've included two pictures, one of the TV with a white screen, and a second with the brightness of the first pictured edited to make the effect more visible.
https://ibb.co/i0zQWn
https://ibb.co/gzxvWn
Does anyone know what is causing this, or know what can be done to fix it?

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