High-pitchy noise?

[Maxim Didur]

Happy New Year everyone! I recently found some recordings on my computer that someone threw to me, and I found a strange high pitched mechanical noise problem. Please tell me what this phenomenon is, which sounds like high pitched mechanical noise and why it appears. I have attached 2 files of each source, the one that microphone is just a pure source, and problem is a file I where planted to highlight the problem to be better heard what I'm talking about.


Microphone 1 - Bm800 + Behringer um2, Microphone 2 - Akg p120 + Scarlett solo 3rd Gen.

Microphone 1:

View attachment Microphone 1.mp3

Problem 1:

View attachment Problem 1.mp3

Microphone 2:

View attachment Microphone 2.mp3

Problem 2:

View attachment Problem 2.mp3