I have an S21 Ultra, an S23 Ultra, and Z Fold 4. We have a dead spot in our home where we cannot use the carrier signal so we turned on Wi-Fi calling. That caused a tremendous echo to the other caller. We tried everything to resolve it, but nothing worked. Someone suggested using a different dialer rather than the Samsung provided one. We installed the Google Voice dialer on each of the phones, and the echo went away.
Hopefully, this will help some of you that have the same issue.
I never had a bad day. Hope you never do either...
