I'm having an issue with horizontal lines on my q60t (QN50Q60TAFXZA). It is especially bad with 4K/HDR content. I think it might have something to do with the latest firmware update. I say this because I didn't notice any issues with my q60t from May 2020 - November 2020. I suspect my tv updated automatically in October/November, around the time when the issue started. I should also say I called Samsung and they sent a service technician who replaced my tv panel on 11/18/2020, but the issue returned after just a week. Oddly enough, the lines move when I change from one picture mode to another. In the pictures I've attached you can see the lines spread apart and become fainter when toggling from "movie" to "dynamic". This makes me think that the problem is not the panel, but some other component or the firmware. I have a service ticket open to make another repair appointment (5126339557).
My tv was serviced twice. They replaced the tv panel the first time and the FFC cable + Assy PCB Main the second time. The repair guy said it was basically a new tv. The issue was never resolved. Samsung finally agreed to a refund, but now I'm waiting for them to pick up the tv. It's been almost two weeks. I'm guessing they are delays because of COVID? I will probably need to call yet again.
Can you provide me with your ticket number? I would love to look into this for you.
100% spot on the same issue i am having with the same model. And like yourself i noticed the issue around that same timeframe. I really can notice it on a dark grey background and turning up and down the brightness moves the lines up and down. So odd. I scheduled a service call but seems like replacing the display only works for a short time. Suppose it could be a frimware issue, but not looking forward to getting this sorted out.
I recommend letting a service technician have a look. Send your full model code and serial number via private message to get started.