for me, this two problems seems like having the same background…
1.) while making phone calls, people hear a strange noise and cant hear me (nearly every second call)
I also could not receive calls sometimes.
2.) want to send a whatsapp msg but it couldn`t send it.
What I tried:
changing sim card
made a hard reset
tried sim slot 2
made all update
I think there is a problem with the connection… (data and phone connection)
this happens on different places, even countrys , so its defenitly not a local connection problem…
thanks for your help