jjb3

Anyone else have the person you are calling say that the sound quality on calls is horrible on their end when using the car to make a call? It's fine at lower speeds, but anything over 40mph is unusable. I called and left a vm for myself and it's terrible. Useless.

arash.re

I purchased C class W206 last week and I experience the same - at lower speed and quite street, the microphone seems to be ok, but as soon as I get to a busy environment or increase the speed, the microphone quality drops dramatically to the point that I have to yell so the person over the phone can hear me.
I had C class W205 just before this purchase and I didn't have this issue with it.
Would be great if you can update us if you manage to fix this issue

jjb3

I had one dealership reinstall the MBUX software and that didn't work. It's now at the dealership where I bought it and they have taken the microphone apart with no success. They have opened a ticket with Mercedes engineering, and it's staying overnight. I will update when I know more.

Serg675

Just have tried at 60 mph and observed no issue. My wife haven't noticed any degradation. I use Android Auto though. It might use Wi-Fi for audio.
A few thoughts on this. Theoretically car speed shall not affect mic reception in any way. The same with Bluetooth. Since it changes with car speed looks like that may be your provider has started to have issues with handling speedy terminals (phones). I would try to disconnect the phone from the car and see if the phone itself have this audio quality degradation with speed.

arash.re

I don't have this issue with my other car so it's definitely not with the phone/provider.
I also got Android, my wife got iPhone on different provider and we both experience the same issue. I am certain that the issue is with the car's microphone/software. I think it fails catching the human voice when trying to block to ambient noise, or blocking ambient noise very poorly to the point that human voice is not easily recognisable.
Seems like not all are experiencing the same issue tho. I called the dealership yesterday and they said few other owners have raised the same issue. They don't know the solution for it yet but booked me for the 25th of July so I can drop the car there (hopefully they can find a solution for it by then).
I'm in Australia, the solutions come here a bit later than the rest of the world 😜

jjb3

Mine is still at dealership. They are waiting on the Mercedes engineers. Meanwhile, the loaner I have has crystal clear calls so its clearly an issue with the car.

arash.re

Any update on this? Did they manage to fix the issue?

MCHonkytonk

I had this issue on a W205 C300 2020 model on the drivers side. Not sure if it made any difference at high or low speeds. Dealer updated firmware, replaced the microphones and the problem still existed. They kept it over night and the next day found that the microphone lead had a fracture. Replaced it and works beautifully. They suggested it could have been damaged in the manufacturing process. Perhaps a heavy handed robot.LOL.

xarzon

Hi arash.re,

Any update or solution for this issue? Mine booked for 20th of Sep.

Estherkimkim

I had same issue and need to replace the microphone. Now its working fine.

Amardanan

Ah, that sounds frustrating! It could be the car's built-in system not handling higher speeds well. Have you considered using softphones? They're apps that use internet connection instead of cellular networks, often providing better call quality. Pairing it with your car's Bluetooth might offer a smoother experience, especially when you're on the move.