Are you sure it is the Screen Reader/Audio Guide (This voice basically reads the text on the screen and verbally alerts you of changed Settings.)
There is another feature that is more of an Audio Narrarator that describes what is occuring on the screen during a movie/show. (ie. Jack jumps over the hill, falls down, kind of thing).
Normally to disable this, you press the * button during the show, select Accessibility and Captions, then select the Audio Track. (sometimes you have to toggle between the different English tracks to discern which one includes the narration). For HBO Max, the audio track used to include the words "Descriptive".
Hopefully that is the cause of your issue.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
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