AirPods Pro inward facing microphone

I'm unclear on how to access the inward facing microphone in the AirPods Pro (not the outward facing one). If this is possible, can you point me in the right direction?

More context is that there is a ticking noise coming a spasm inside someone's ears that I'd like to try canceling for them.

The standard AirPods Pro noise cancellation modes don't have any effect on the sound.

I know latency may be too high to do this on the phone with a custom app, but thought if I could reach the point of that being the problem, then I could experiment with predictive algorithms.

Thank you in advance for ideas or recommendations.

have you had any success elsewhere ?

AirPods Pro inward facing microphone
 
 
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