I see that "microphonics" is indeed the popular term for this phenomenon. To be pedantic, microphonics was originally used to describe inducement of electrical signals in wires, similar to how a microphone works.

https://en.wikipedia.org/wiki/Microphonics

> Microphonics, microphony, or microphonism[1][2][3] describes the phenomenon wherein certain components in electronic devices transform mechanical vibrations into an undesired electrical signal (noise).

There's no electricity involved in this phenomenon, which arises through pure mechanical coupling when the wire causes the sealed earpiece to move and air pressure in the ear canal to swing wildly.

But that's like complaining about URL vs. URI...