I thought that perhaps Apple would do something about it as well, since it seems to be such a common problem. But this is the response I just got from Apple tech support:
"Software updates would not effect hardware really , the update would be coincidental to the mic going out honestly. A firmware update would be different but just a new OS will not cause hardware failure."
I said that in reading the Apple Support communities this seems to be a very common problem, and I was told that they're sorry, they can't help me with a bad mic on a product that is out of warranty. Way to stand behind your product, Apple! 😟 I understand electronics aren't going to last forever, but I DO expect higher priced items to have a longer life.