2020 QLED T models (Q80T, Q90T, Q800T, Q900T) HDR game mode brightness / local dimming bug

[Rauttis]

I bought a Q80T a couple of days ago and have noticed a really annoying issue when using the tv with the combination of HDR and game mode.

I'm fairly certain this is a software bug in the TV since I can reproduce this issue with 100% accuracy, and it happens on the dot at the same moment every time. It's basically on a timer.

Basically when the game is displaying a HDR signal and game mode is enabled, exactly after 6 minutes the brightness of the TV suddenly drops by around 20 (50 -> 30). The value of brightness setting doesn't actually change however. Messing with the brightness setting does not restore the brightness to it's original state, but changing the local dimming setting from standard to low and then back to standard does. Switching game mode off and then back on also fixes the issue, but then it happens again EXACTLY after 6 minutes (I've timed this with a stopwatch).

Has anyone else experienced this issue? Or can someone maybe test this on their TV to see if you can reproduce it?

Exact repro steps on how I can reproduce this 100% of the time on the PS4 Pro:

1. Set brightness to max (50)
2. Set local dimming to standard (bug happens on high as well)
3. Enable game mode
4. Turn off game motion plus
5. Turn off intelligent mode and all the brightness related settings in eco settings, as these can influence the brightness level of the tv.
6. Launch a game that runs in HDR
7. Start your stopwatch
8. Do whatever you want in the game or you can also go back to PS4 menus, find a bright scene where you can notice a brightness drop easily
9. When the stopwatch hits 6 minutes, you should see the TVs brightness suddenly drop by a large amount. By eye the brightness drop seems about equal to dropping the brightness from 50 -> 30 by hand.
10. Go to picture settings and set local dimming to low (brightness does not change)
11. Set local dimming back to standard (brightness suddenly jumps to the original level. Brightness can be restored by switching input away and back as well, or by disabling and re-enabling game mode)
12. And again after EXACTLY 6 minutes the bug again repeats and the brightness drops down again

Some other notes: The PS4 has a screensaver that basically dims the screen if it is idle for a while. This is not the cause of this, this happens even when the console is in active use and the brightness can be restored temporarily by changing the local dimming setting like described above. I have not managed to reproduce this issue with game mode off, so it seems to be related to game mode.

Software version: 1304

[WackyHackster]

@NickHwd  This had me in stitches, well played!

[QuantumP]

Still waiting on some response from Samsung. No updates, they just don’t communicate with their customers.

[AV2020]

I have been following this thread since August but now I am so confused as to what this thread is all about now. It seems everyone is frustrated with each other and that users have still not had their voices heard by the manufacturer. It seems like everyone argues with each other on here in hope that the manufacturer will fix the issues. 

Not sure what to make of this. 

[IamPeacock]

What do you expect, when Samsung remains silent. We're all that we got.

[AV2020]

Where is the guy who works for Samsung? He seemed helpful and updated regularly on what is being fixed and when? It has gone quiet lately. 

[daparky]

I am so confused with mixed reports of game mode on this years range. Some say it's bodged and others say it's perfect. This video for example: https://www.youtube.com/watch?v=zDlWbuxh8J0

I see no issues what so ever?

[Soccercrazy1]

So after I downloaded the update to 1402.1 for over a week now I have come up with some findings. 

First thing is that dimming bug never happens anywhere.

Second thing is that local dimming is better now. Turning on GMP makes it even better than having it off but both are better than pre update. There is still lots of bleeding but it is acceptable. 

Also if you turn on GMP, the color does fade out slightly. However, if you move either the blur reduction or judder to just 1 then you will get your color back. I don't understand why but it is what it is. 

Lastly HGIG is a must use. It greatly increases contrast and makes a more dynamic image. 

I saw there is a October version of the update so I downloaded it and it is a different size than the one I installed in September last week. Anyone know if it does anything

[Snir4]

You from us?

[Suríya]

He is. I have the latest firmware that was given to me personally.

[Soccercrazy1]

Yes I'm from US