What is that sound?

Hello. About a year ago I noticed strange sound oustide of my window, I tried to walk around my district to see what's causing it, but couldn't determine that. Lately it become so loud it's impossible to sleep without plugs or just sit home with windows open (and since it's a hot summer - that's kinda hard to to).

There should be a video attached to this post with this sound.

https://reddit.com/link/1ugw16m/video/9c922a960s9h1/player

Do you happen to know what causing this sound?

Last time I asked one single person assuming this is ventilation system, but I never heard anything like that before