What causes muffled voice issues in CarPlay after iOS update?

Hi All,

I use Apple CarPlay in my car with my phone connected via USB. I make calls from my car. some months ago, the people on the other side of my calls started pointing out that my voice sounds muffled, far, and quiet when I speak. This only started happening after updating iOS. I am not sure which update caused this issue, but it is clearly the only reason at this point.

For your info: I took my car to the dealership today. The technician at the technician diagnosed the problem. He connected his android phone, via USB, to my car and made a call using Android Auto. His voice was clear to the call recipient. He ran the test again using another android phone. The technician had the same good results. Finally, the technician connected an iPhone that is up-to-date and called the same recipient using Apple CarPlay. The voice was muffled and far.

The dealership inspected the mic and did not see any issues with the setup. The car is new and nothing has changed in the setup

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