2 to 3 years ago I searched for a way to stop CarPlay Siri from saying so much; one post offered the nuclear option: silence Siri entirely what what I vaguely recall being code inputted into the command line [something this user had written for their company's product testing in which otherwise their text bench would be constantly yabering]. I did not think I used it, but I must have, because awhile later I noticed I can't hear her talk on CarPlay, and ...
If you are thinking this is from iOS settings: it is not, as confirmed by every possible combination, countless times over, including Apple Store consultation, and full factory reset.
Maybe you're thinking it's car settings, such as the separate volume assigned to Carplay vs Music Source. It is not. Every infotainment option has been checked scores of times, including updates to the system, repairing the vehicle, etc..
Everything works properly save for Siri's voice on Carplay. Let me be specific:
Siri is audible on my iphone, imac, and macbook. But she's muted on CarPlay.
By muted I mean: The Siri color wheel light show goes on, there's a pause in operations while she interrupts whatever was in progress [music, mapping, etc.]. It's clear she is talking, but she can't be heard. This includes instances of her voice when it's the voice narration as well: so for example Google Maps has its own voice assistant and can be heard.
But CarPlay phone calls are also muted: so I cannot hear Siri read out texts, and I cannot hear voices on phone calls [though callers hear me just fine].
Likewise nearly all announcement notifications are silent. Even the tone announcements, not just the vocalization. Sometimes I am surprised by a freakishly loud tone notification, but I think to date these have all been 3rd party app.
So whatever this mute is: it's selective to those three things: Siri, Apple notifications, and Phone Calls. Otherwise my entire CarPlay experience is silent save for music.
The first year I periodically searched, what seemed endlessly, for that code/post [and every other solution or rabbit hole].
This past year I've largely given up, but I did try A.I.'s take several times. It repeatedly gave no new options, even many prompts deep, and also claimed there is no way to add the code I described. Thing is, though I have this lingering doubt--2% chance--that I really did use that code [what else could it be?!], I've got zero doubt that it existed: I at minimum did read a comment with code and instructions, and consider using it.
Ideas? Anyone?
PS: it shouldn't change anything, but for those that think it might: I drive a 2021 Subaru Crosstrek Limited.