What are you referring to as "screen reader"?
What Roku calls Screen Reader formerly was called Audio Guide. It provides voice overlays to the audio of the current screen to announce where you are in the Roku menus for the benefit of the visually impaired. It can be toggled on and off by the shortcut of four quick presses of the * button on the Roku remote. The shortcut can be deactivated altogether via menu path Settings > Accessibility > Shortcut (in the Screen Reader or Audio Guide section) > Disabled.
Since you mention "words are on screen", might you be asking about Closed Captioning, where the spoken words are also displayed in text on the screen? The default location for Roku's closed captioning controls is via the * key on the Roku remote while viewing a program. Some channel apps don't use the Roku defaults, instead substituting their own method of access -- I'm guessing this is so they will have consistent controls with versions of their app running on platforms other than Roku. Often these options are accessed by pressing the up and/or down cursor control keys while viewing the program to pop the channel's own control options on the screen.
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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