ue43au8000 - brightness keeps auto adjusting at start of scenes.

[MattKB]

Hi all,

Bought the ue43au8000 the other day and have noticed that on Disney Plus, watching some content I get a weird shift in brightness at the start of a scene change. Example would be Thor Ragnorak on Disney Plus (tried the native app and via Fire Stick). Example video below (you can't really tell it too well on this video).

https://youtu.be/OFnch3en4Mo

I assume it's something to do with the HDR. I tried turning off the auto brightness thing in power settings, motion brightness, and tried different screen modes, and it still does it. I've also tried changing the picture mode, when the quick select menu is up, it doesn't do it, but as soon as you go back to watching normal, it does it again.

There aren't that many settings, so I can't see why it's doing it. It does it on all picture modes, Standard, Dynamic, Movie etc. There must be something obvious going on but can't see what or why. 

[AndrewL]

@MattKB: I'm sorry to hear that you're experiencing this issue. Please can you try heading to Settings > General > Intelligent Mode Settings > Adaptive Picture, and toggle this option off, as this optimises brightness and provides the best picture quality in real time, based on the lighting condition and the
content you're viewing. Furthermore, head to Settings > Picture > Expert Settings > Local Dimming, and set this to Low, or Off. Also, try Settings > General > Power and Energy Saving > Brightness Optimisation > Off > Brightness Reduction > Off > Motion Lighting > Off. Let me know if this helps. 

[MattKB]

Thanks.

I dont have an intelligent mode settings option, nor do I have local dimming. I do have the power energy saving setting though. They are all turned off. 

[BIBURYBILL]

https://youtu.be/oGHmUHEVMD4

[MattKB]

Thanks. I’m happy with the picture settings , and the brightness optimisation etc is all off, but I’m still getting this lighter darker flickering. Latest example is in the end credits of Wheel if Time on the Amazon prime app. 

I assume it’s something to do with the hdr?

[MattKB]

Here’s a better video showing the problem. Tried built in prime, and disabling the input signal plus on the fire stick - has the exact same problem. Auto brightness optimising is off, all the power setting energy stuff is off. It’s terrible!

[Robotomatronic]

Same issue here too. Even turned off the dynamic contrast settings but still same issues. This only seems to happen on external sources and not with the built in apps.

[MattKB]

I found a solution. You need to access the tv service menu. Do not tweak anything other than the settings below or you could cause significant problems.

Turn the TV off. Then press 

Info, Settings, Mute, On

From another forum:

“Navigate to SVC > Other Setting > CAL Data Restore and select this option. There will be a USB error message, just click ok.

Back out to the main service and you should see an "advanced option" now listed at the very bottom. Highlight Advanced and press volume up USING YOUR NEWER SMART REMOTE for 5 or 6 seconds.


This should open more options below Advanced.


Move down and select Picture_2D > Subsetting, this will open the important menu.

You will be changing PWMINI 2D and PWMMOVIE INI to a higher number. I suggest moving from 30 to 75 or 80 and 15 to 75.”

Apparently there is some slight dimming still at 75 but I can’t see it at all. Fixed it for me. 

[John Silver]

I made an account just so I can reply thank you.

I was about to send the TV back to the seller but said lets google this one more time around 3 am before asking for a return the next day or so.

This solution works for me on a UE55AU9000.

It is totally embarrassing Samsung burries it in some obscure service menu that's harder to bring up than Sub Zero's fatalities.

I knew this will be PWM related, I recorded a video when the screen dims and I could see the flickering.

Thanks Matt.

[MattKB]

Glad it helped! I spent weeks searching for a solution and cobbled it together from various other forum posts and YouTube bits. Glad it worked.