Question Rattling Sound, CPU?

Jan 7, 2021

That is the sound right there, the sound is very inconsistent and just started up again this morning.
I had thought it was the PSU, since I had loosened the screws that hold it. (The first rattling occurrence was close to when I loosened screws)
But the recording was taken right above the CPU and it was much more clear than near the PSU.
(The PSU may have to do nothing about it but I just felt like this should be said)

It could be dust but I am afraid it's a heat sink or fan problem, unlikely since it hasn't even been a year since I built the PC.
Additionally, I put my fan on near the computer and a while later the rattling sound went down so ¯\(ツ)
I assume the second I go back on the PC the sound will vanish but that's exactly what happened before.

I just need clarification what the sound could be caused by.