Was the phone audio sounding as if the voice was coming from somewhere behind the front firewall of the car rather than through the cabin speakers -- muffled and bass-ridden?
This happens to about half my phone calls lately.
It's but another of these random bugs that are increasing in one system or another in the car as these updates continue. (I'm also having the problem with all audio in the car, including turn signal sounds, disappearing. Well, the turn signal sounds are not actually disappearing. If the car is not moving and no one is making any noise, you can hear them very, very faintly, as if they're coming from somewhere in the front right footwell.)
This is getting really, really, really tiresome.