Asus ROG STRIX fan buzz

Hello, today after some hours in my backpack my laptop CPU fan started to make funny whistle/buzz noise. Here it is:

https://youtube.com/shorts/a8G0F5KqqgU?si=gX7fcXIQNpK1nFOh

Any thoughts? I'm not really annoyed by the sound, but I just don't want to damage anything by leaving it as is.