Sound distorted when calling and receiving calls

Hello raul2020! Thank you for participating in the Apple Support Communities.

We understand that after updating your iPhone to iOS 15, the sound is distorted when on phone calls. We'd like to look into this with you to see how we can help. 

If this issue is happening with your iPhone only, and not while using headphones, the following resource may help: If you hear no sound or distorted sound from your iPhone, iPad, or iPod touch speaker

If this is happening while using headphones, let’s try the steps outlined in the following article: If the sound from your wireless headphones cuts out or is distorted

Make it a great day!

I have the same difficulty since updating to ios15. Calls sound distorted to me and people struggle to hear me. No problems when using Bluetooth in the car so it’s a handset issue. Any advice on how to fix this?