I know that this is a bit old, but I've had the same problem for the 18 months I've owned the phone (2020 model).
- As far as the mic goes, I still have the problem using bluetooth earbuds or wired earbuds, so for me it's not the phone's mic.
- Like the op, I take most of my calls at home, where it happens on every phone call. I have found that if I move away from my desk/computer it seems a little better, but not completely gone.
I know that when I moved in here and had AT&T (10 years ago), the reception was horrible, so I switched to Verizon and it was never a problem. A few years ago I went with a cheap service that uses both networks, brought my old, cheap ZTE phone over, and
still had no problems. For xmas 2020 I treated myself to this (unlocked) phone, and it has
always been a problem.
Remembering that the only other Motorola I ever owned back in 2011 had horrible reception everywhere I went (and was returned), I've come to conclude that Motorola has some weak antennas that don't perform well where I live, which is essentially on the border between suburbs and rural. Maybe the towers are a bit further apart here and this phone doesn't pull the signal as well?