Same problem here, 2020 Model 3. The Other end of the phone call cannot hear me at all when I make or receive calls, different people/phone types. yet the cars Voice commands work for other things. This has been a sporadic issue for the past couple weeks. Prior to this particular issue, I was told I sounded like a robot on a handful of occasions by different callers. I chalked it up to the cell service at the time but now I’m not too sure.
Does this happen often with sw updates? Is there known faulty hardware?