Integrated Microphone no longer works

On Fedora 33 Silverblue, the integrated microphone with my Lenovo P1 (2nd Gen) stopped working with version 33.20210302.0. This would fail occasionally when running various applications (Cheese, Google Chrome in a toolbox).

How can I help diagnose the root cause of this? Working microphone is an absolute requirement of an OS these days.

Filed bugzilla 1937417 – Integrated Microphone stops working when headphones are plugged in