S21 ultra stuck on 120 Hz and draining battery

[BroTony]

My S21 ultra is constantly at 120 Hz it doesn't even switch to 60 when watching videos. This has a huge toll on my battery. I'm getting 5 hours of battery when I used to get around 8. I'm using the exynos variant in the UK btw,unlocked. I had the January update on 13 Jan. 

[jayboi54]

Mine worked for a while now gone back to being stuck at 120

[BroTony]

Mine is still fine. Samsung has to solve this issue. The battery drain is just too much when your phone is stuck at 120 Hz

[jayboi54]

When the brightness is low its stuck on 120hz, and when I turn it up to just over a quarter it works OK, mad

[Members_dNTDx4q]

Hi, I have the same unlocked exynos variant, and my problem occurs in 2 different ways:

- screen stuck at 30 Hz

- after restarting the screen, it stays at constant 120 Hz

I am very mad at you Samsung, I have this problem for 2+ months now on a 1200 eur phone! Somewhere I found an adb solution, and with direct system settings write it could also be resolved. I uploaded the instructions to my website and also created an (open-source) app:

https://szirakiapps.com/#/refresh-rate-reset

For me it works fine, just open the app and press the button, however, the problem comes back after some time. SAMSUNG please fix it!

[Anonymous User]

there is a simple workaround
s21 ultra screen adaptive refresh wont work unless you increase the brightness

above maybe 20% if you dont like the higher brightness specially in night

just go to accessibility and toggle extra dim and move the slider to max

and thats it the phone brightness will be above 20% and that will activate the adaptive refresh rate and the extra dim feature will make it look like you didnt raise the brightness

[Cătălin2020]

Ok guys, the problem is the ambient light sensor and a buggy samsung software.

In low light ,your screen won't work with adaptive refresh , it will be stucked at whatever refresh you previously used before light sensor will tell to the kernel that the ambient light is low,be it 48/60/96/120 Hz , in most cases will be 120 Hz.

If you use the phone in a well iluminated room, or into daylight , adaptive refresh will work just fine,but in dark places or low ambiental light,it won't work at all. 

If your phone is stucked at 120HZ,just iluminate the top of the screen where the light sensor is placed  (not just rise the brightness of the screen) and you will see refresh of the screen going down to 60 Hz again.

I don't know if samsung is aware about this issue