The dehumidifier.
The fan on the external hard drive.
The fan on the desktop P.C.
The fan blowing air through the otherwise stultifyingly dense office air.
Incredible amount of white noise for such a small room.
I detest the stuff.
Earplugs?
Black noise?
Soundproof housing for all computers using fans?
AAAAAAIIIIIIIIIEEEEEEEEEEEEEEEEEE.
Cartooniverse
Put on some (low-volume) music and chill, my man. 
Wait for the next power failure and revel in it. 
No no no. That’ll just mix with the white noise and create grey noise, which is even worse than white noise.
What you need is some black metal. Round up some Dimmu Borgir, Rotting Christ, and maybe some Marduk. Play it as loud as you can until someone complains, then turn it down just enough to placate them.
Weird. I love white noise, and can’t sleep without a fan. Hmmmmmmmmmmmmmmmmmmmmmmmmm. Ah.