No PC mike needed.
When I did work-from-home there was a dial-in number for meetings, with an access code that everyone (including the closed-captioning transcriber) had; everyone called that number and entered the code to join the meeting.
We used company-issued laptops with the microphones disabled; work was a major defense contractor, so they were paranoid about snooping.
Captions were accessed by using the caption service website.
> microphones disabled
How?