The mic has been knackered on my iPad Pro 12" v1 for a good while now :-) and tonight the virtual keyboard went funny for a few hours, no response to presses on the on-screen key images. In the end two reboots fixed the virtual keyboard response. The first reboot did not do it. I think what was needed was to close all apps and run reboot, so it does not reopen them in restart. Just a theory.
One odd thing was that it was a lot better in portrait mode than in landscape.
Talked to Apple via chat who were pretty slow. They are arranging a mail-in repair assessment. Hopefully the keyboard thing will not come back. But the mic needs fixing definitely because I cannot use Siri, which save my hands and helps me when I am very groggy and full of pain.
I am not sure what happens next. They said that I should wait for an email with further destructions.