Some programs include soundtracks in alternate languages. Some channels will retain this setting from program to program.
The Roku default method of accessing your choice of audio track is to press the * key on your Roku remote while viewing the program and examining the options presented.
But more and more channels are not using the Roku default but 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. I don't happen to be at home to check how Disney+ does this. 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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