Q7F vertical line flickering defect


Novice Member
I've been experiencing some odd defects with my Samsung Q7F recently, as demonstrated in the video below.

These flickering lines come and go with relative consistency dependent on what the TV picture is showing at the time— this seems to occur when there's a bright area on screen in the top right corner with a somewhat darker image beneath it.

My technical knowledge is limited, but I do know that the Q7F uses ten vertical bands acrosse set's width in each of which a poor man's local dimming effect occurs. This defect occurs exclusively in the rightmost such band.

I do experience another defect though. This time in the second band along from the left. It's different from the first in that this time the entire band simply appears a shade less bright than the rest of the picture. This defect comes and goes and does not seem at all dependent on what's on display on the screen — when it's there it just stays there permanent, it might be there for a solid hour or whatever, and then it disappears.

These defects occur frequently on all inputs and as far as I can tell cannot be muted by altering picture settings. Both defects never occur at the same time though, it's always either one or the other.

Anyone know anything about this? I've searched but found nobody reporting anything similar. The TV is second hand so it's not like I have can just send it back — my main worry is that this cannot be repaired without a full screen replacement, something I cannot afford.

Thanks in advance.


Distinguished Member
You mentioned it's second hand. Have you had it long, and if so has it been working fine for a long while?

There's always the possibility this issue could have been the reason for the sale to begin with. Unlikely though if you've been using it fine without issue for a good amount of time.

If it was me buying second hand, I'd want to get extra warranty. Many retailers offer a 5-yr warranty. The seller may be able to transfer this to you by contacting the retailer. If there is no extended warranty, then you need to know the original date of purchase, as you should still be able to get a repair, replacement or refund with a receipt dated less than 1-yr old.

Edit: Always worth troubleshooting too. Try new HDMI cables, different ports on the One Connect box. Also, make sure to try the TV apps for Netflix, YouTube etc. just incase this might rule out a fault with the One Connect box.

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