Just yesterday we let you know that Samsung has acknowledged lag issues affecting some Galaxy S21 units, especially in the US, after being updated to the stable iteration of One UI 4 based. on Android 12, whose rollout began last week.
And today, the company already has the solution. The problem was, when selecting 120Hz in settings, the refresh rate would revert to 60Hz after the user stopped touching the screen, resulting in a lot of perceived lag.
The new version is G99xUSQU4BUK9 (where “x” is different depending on which S21 family member you have), and it replaces the old G99xUSQU4BUK7 on US carrier models. For now, the new build has presented itself to Verizon, but we expect it to hit units from other carriers very soon.
As the aforementioned refresh rate switching bug appears to primarily affect the US units of the Galaxy S21, S21 +, and S21 Ultra, it remains to be seen whether this hotfix will be released globally on time or not. People who have already installed it report a major improvement in the overall responsiveness of the phone, although there is apparently still some residual scroll lag in third-party apps.