Hi All,
I had a the same issue with crackling noise on the receiving end using my Iphone 7 in a VW Arteon 2018.
I sounds like an software problem with the noise cancelling failing. I soon as you speak yourself, the noise is gone.
I did the following:
I tried an Iphone 5s : works
I tried an Iphone 6: works
I tried an Iphone 7: works:
I tried an Iphone 7 plus: works
All different service providers and sim cards
Convinced it was my phone (my specific phone) I went I trying a new Iphone 7 plus. On entering my sim card. same issue again.
Then I tried my simcard in my wifes Iphone 6: and suprisingly It was bad too.
How on earth can the simcard be an issue here? I cleaned my simcard using contact spray, placed it back in my 7. Gone was the problem. It took me a week to get here.
I am still somewhat surprised. What also can be the case. I have read on other forums that specific providers might have issues. So the answer in my case might be eighter the simcard itself making a bad connection. Or more likely: by chaning the simcard you force your phone updating the service provider settings, whilst setting things right.
I am still in a bit in disbelieve that this is what sorts out the problem. I will be testing more next week. This is what I did. Maybe it helps for some of you too.
Good Luck!