@Wosie-
The power, volume, and mute buttons on current wifi-direct Roku remotes send the appropriate signals to your TV via line of sight infrared (IR) signals.
Different tvs have different sets of IR codes they accept, so you have to set up the remote to find and send the correct code set for YOUR tv.
Roku menu path: "Settings -> Remotes & devices > Remotes".
At this point if your remote has already been setup for the tv but you need to reset it, arrow down to select your Remote (in use).
Now select "Set up remote for TV control" .. And follow the prompts.
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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Ultra 4800 | Streaming Stick 4K+ 3821 | TCL Roku TV 43S245/C107X
