I have the same problem.
People tell me it's soo bad they have problems understanding me.
I am not using the loudspeaker.
If I use headphones, the problem is not there.


Interestingly only when I use the normal phone.
If I talk to people on whatsapp, the echo doens't seem to be there.

I'd like to see that as well.
Especially since the phone is an outdoor/emergency kind of phone.