@SDG72
The CEC 1-touch feature for Roku is located under Settings/System/Control other Devices
However, I believe some users that experienced this issue with Samsung TVs traced issue back to the "Universal Remote" setting on the Samsung remote.
Go into your TV settings (using Samsung remote, not Roku remote) and see if toggling off the Universal Remote (or similar language) helps you out. Appears that this Universal Remote setting may be viewed by Roku as simulating a Play/Pause action that activates a function with a lower left ad on the Roku Home Screen when present.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
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