The Roku model# is C122X on my TCL model #43S42. I am currently running Roku Software version 9.3.0- build 4182-93.
I first noticed this line/bar when I initially purchased the tv, but it only happened twice and I was able to restart the streaming app to get it to go away. Roughly a month later the line would start to appear on streaming apps once one program or episode ended and then another began and would persist only until I turned the tv on and off. The only thing that fixed it was a power drain. The first fix lasted for roughly 8 hrs and then appeared again. So I then tried a soft reset and the bar would show up almost immediately in all streaming apps. I once again did another power drain and it has not showed back up since. I did this almost two months ago. It seems that this line only started to become a problem whenever the tv was left on for prolonged periods of time which it has not been lately.
I don’t believe it happens with any kind of specific streaming like 4K or HDR, but I cannot be sure. It showed up for me in multiple apps and I don’t think adult swim is either 4K or HDR, but I could be wrong.
I don’t think I had the TV set to any kind of Picture mode, but I do believe that I had adjusted the picture some previous to this issue happening. After the soft reset I never changed the picture again, but like I previously mentioned it did however show back up after this soft reset almost immediately after opening any streaming app until I did a second power drain.
I hope my answers will be of help to you and getting this problem solved for others and to prevent it from happening again for those of us it has currently stopped affecting. Thanks.
