I downloaded, installed, and configured the app: "RemoteControl for Earphones"
I tested my mic....and it worked....however the high pitch output persisted. HOWEVER....
When I held down the middle button on the Earpods while plugging in the headphones to my phone, the microphone worked AND the high pitch was removed.
Quirky and a little bit of a pain but I may just end up keeping these instead of tossing them and getting something else.
Further discussion on this topic is welcome.