Noisy NZXT fan on startup

[photon05]

Hey all,

I have a NZXT S340 case and the two fans that came with the case have been rumbling on start up. It usually dies down after a minute or so or after I give the fans a solid tap. I've heard about using 3-in-1 oil to lubricate the bearings, but when I tried to do so, I saw that the fans were different than others in that they don't have the bearing exposed : https://unsee.cc/00b06c91/

Anyone have any tips on how to lubricate this thing? Or even another way to stop the rumbling? Aside from replacing them, of course.

Thanks!

 

[Ralston18]

Just try tightening and loosening the mounting screws. Do so carefully and in small increments.

May just be some vibration pattern..

 

[photon05]

I've tried that a few times actually. All it does is make it noisier or a bit quieter, but it's still very noticeable.