I purchased a NU6900 4K TV 7 months ago and it worked flawlessly until this morning when I turned it on I noticed it seemed sluggish, then a notification popped up indicating it finished installing a firmware update, okay cool explains why it was running slow. HA! Guess again!
My TV has been a total nightmare, I spent 5 hours of my day off trying to reset it I've done every method I could fine online nothing is working. It flickers on after pressing the power button 20+ times with a quick splash page then shuts off. Sometimes it will come on and even show the home screen of my Xbox but it won't connect to the remote even though the remote is producing a signal.
Coloree pixels and lines will flicker and flash across the screen then it will freeze and shut down. I cannot get to the settings page to do a factory reset.
I called support and the woman I talked to actually gave me attitude, like seriously? I am so fed up with this company I will never, ever purchase anything Samsung again and will boycott/rub their name through the mud to all my friends and family to make sure they don't have to go through this.
To anyone who hasn't experienced this update please turn off your automatic updates. Looking through archives this was a common problem in 2017 which Samsung kept under the rug and remained hushed about.
I don't know your particular problem, and maybe you have done this, but if not: unplug the power cable to your tv (and maybe consider disconnecting all cables from it, i.e., hdmi and such). And then reconnect the cables. And then reconnect the power cord.
I am only mentioning this because my Samsung soundbar was working flawlessly until the firmware update on 7/3. And after ALL other troubleshooting possibilities, including Samsung chat support, I disconnected everything again, but also disconnected my tv power cord. I reconnected everything back just as the manual said (tv power cord last), and my soundbar was back to putting out sound.
So sorry for your troubles.