Callers cannot hear me (distant, tunnel sound)

Callers claim they cannot hear me when using these buds. Pixel 5 phone, up to date, using the galaxy wear app, reinstalled and re-paired.

I suspect the microphone may have gotten damaged from frequent wipe downs with rubbing alcohol early in the pandemic, but I cannot be certain (and alcohol doesn't usually cause too much damage...).

I took a look at this teardown Samsung Galaxy Buds+ の分解 but I'm not sure if damage to the mics would be obvious or not.