Duplicate of https://bugs.mojang.com/browse/MC-120952, which is marked as resolved, but it's not.
Setting speech volume in Audio settings does not change volume of the Narrator. Narrator is ALWAYS at 100% volume.
Setting a different voice in the old Windows narrator settings (accessible through the old control panel > Speech recognition > Advanced speech options > Text-to-speech) does change the voice, but there are no volume controls.
Thank you for your report!
We're actually already tracking this issue in MC-118470 and MC-118526, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main tickets it would be appreciated.
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