Title is not great I know. Was supposed to say "no clear cause" but accidentally posted
So I have recently been having a loud rumbling noise from time to time on my Series X. It would get a bit loud, then quiet, then loud again back and forward. I figured something was clogging the area around the fan or otherwise dust clogging the heat sink, making it work harder. So I opened it up to clean it out, nothing too terrible, but it's arguably worse since it's now constant.
It's worth noting that this is a fairly old Series X, so it could just be wear and tear. I've also only just recently started having the Xbox stood up instead of lying on its side, if that's also worth noting.
Video is attached for sound reference. If anyone has had something similar, I'd appreciate advice.