@DjDazza: Does the issue occur on inbound calls, outbound calls, or both? Also, are you encountering the problem with particular contacts, or in a certain area, or is it persistent? If you place the call on Speaker, do you notice an improvement?
This worked for me and it was related to the microphone not working properly on the S21.
1. Pull down drop down menu. 2. In the top right, click the gear to go to settings. 3. Scroll down and go to apps. 4. Click on the phone app. 5. Hit Force Stop in the bottom right 6. Select OK. 7. Click on Storage 8. Click on Clear Data 9. Click on Clear Cache 10. Select OK
Hi - I have the same problem with my S21 phone. After 2 minutes the sound from the other end becomes distorted and I can't understand anything said. This problem is on both incoming and outgoing calls and is not related to the microphone as the person on the other end can hear me ok. I've tried everything I can think of including safe mode and removing protective case. This is the second S21 I've had with the problem and Amazon replaced the first one, They now want me to send it in for repair to Olympic Shavers, their repair centre? I'm not happy to part with the phone and have no confidence they will find the issue. I've tried Samsung troubleshooting FAQs and there isn't an option for my problem. I use bluetooth hearing ***** which I thought might be the problem but the fault also occurs when I don't use them at all. The fault can be heard on loudspeaker and internal speaker and I've changed the SIM too. Help!!