Just to make sure I understand the problem, do you mean that when you set the refresh rate in Settings to 90 Hz it is later found to be set to 60 Hz?
Is any battery saving app or function active?
Is any video or gaming app being used that might be changing the setting in the background?
Although the display renders at 60 Hz, com.android.settings does not indicate this in the relevant context menu’s circular checkboxes. Consequently, the user must select 60 and then 90 Hz to remediate this.
Battery Saver is set to “No Schedule”.
I don’t know of anything in existence which might fit this definition.
I suggested using Safe Mode to see if the problem is coming from a user-installed app.
Another thing would be to enable Developer options so as to activate the function “Show refresh rate” which permanently displays the refresh rate in the top left of the screen. This would enable the user to immediately observe a change and hopefully associate that with some event. If you do this make sure you instruct the user to not change anything else unless instructed, and to keep a record of all changes made (when, what).
I have enabled this on my own phone and will keep a look out for a few days, though I don’t really need the higher refresh rate.
You say that the setting gets changed “randomly”. It take it that just means that the user doesn’t know the cause and hasn’t yet associated the change with some event.
Does “temporarily” just mean “until the next apparently random change” or does it mean until the next reboot, or something identifiable?
I understand your brother notices the screen renders at 60 (while using some app?) although 90 is selected in the settings and I was wondering how he notice (if not with the dev setting mentioned by oldroutard)
I had the setting on for 2 days and it stays at 90 all the time according to this, only Google Maps degrades to 60…
Neither he nor I know of it consistently activating in any specific applications, and it remains when in Settings when checking the refresh rate selected, which is why determining whether it is being a problem is easy. Strange that it consistently degrades for you in Maps – that seems like a separate issue, and probably caused by certain applications deliberately restricting the refresh rate?
The refresh rate of my phone has been set to 90 Hz for a week, using the dev setting to display the value permanently. While the rate is reduced to 60 Hz when the screen turns on after a period of sleep, it immediately resumes a value of 90 Hz and has shown no tendency to randomly switch to 60 Hz.
I think it is likely that some apps will reduce the rate while they are in use, as observed by Yvonne.