It's accepted that some TVs have better tuners. But folk can't live with it must return the set since I've yet to find any maker swap tuners unless the tuner is dead. Sorry but that's my observation so far.
Bob
Once in a while I see a field of purple horizontal dots, usually in stacked, spaced, horizontal lines, in proximity to tiles on a Windows 8 start menu. I'm running 1280x800 over HDMI1 set as PC. This issue crops up when cold or warm. Power cycling the TV clears the issue.
I decided to compare my SEIKI's tuning ability against the Samsung and when tuned to the same ATSC channel, I observed the Samsung showed an inch high line of garbage pixels across the top and staggered interleaved frames about 4 inches apart vertically about the rest of the screen. The effect would come on and off between transitions. The SEIKI had no issues. Power cycling the Samsung TV cleared the issue.
In both cases, I grabbed photos and videos depicting the issue.
Is this a known issue with newer Samsung sets? I read about purple artifacts on older HD Samsung TVs.
The issue does not happen predictably and I have not found a way to recreate it manually. Samsung chat has asked for a picture test followed by a factory reset. I will abide, but I am not optimistic that these symptoms will be cured by a factory reset.
Samsung support informed me they have not received any reports of this issue, and I wondered if anyone else sees this issue with their Samsung UHD manufactured in or around November 2014.
FYI, from worst to best ATSC tuning: Samsung UHD 40, SEIKI UHD 39, Vizio 720p 26".

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