This is easy to overlook ...
When setting the resolution, when you get to the countdown screen click on the "yes" option to save this setting to the Roku.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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Streaming Stick 4K+ 3821 | Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X
