It may be that the program you're watching has "audio description", an accessibility feature where when there's no dialog, the scene is described for viewers with impaired vision. Usually this can be changed by changing the audio track. In many Roku channels, this is done by hitting the star button while video is playing, going to Accessibility & captions, then going to Audio track and changing it. As you move through the track list, the highlight will indicate the language, but the text at the top of the list will indicate if it's an audio description track or not.
Some channels have a different way of changing audio tracks that's specific to the channel.
As mentioned, 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. 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. If this post solves your problem please help others find this answer by clicking "Accept as Solution.".
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