Sounds like someone who can’t type playing with an oldish electric typewriter. It’s too late to borrow a cat, I have a fire extinguisher handy, anything else I should do?
Call animal control…sounds like you have racoons, or wild secretaries. lol
Listen carefully; do you hear ominous music?
If so, take the one girl who’s a virgin, grab a large knife or machete, split off from the rest of the group to investigate/have wild monkey sex. This is absolutely the right decision for longevity of your life as sacrificing the virgin always means the deranged killer hiding out up there will leave you to live.
Although I don’t believe in ghosts, I once had a ghostly encounter that involved a typewriter. And another one with horses.
I was waiting for you to say it was Smith-Corona.
It Placed in the 3rd and paid $3.80.
Hmm. I heard a scratching noise in my bathroom yesterday. Right near the big hole in the dry wall, behind the vanity.
I was hoping it was a cat. Not because I want a cat. Because…the other possibilities seemed worse.
ETA: If it was a cat, it would have been able to get out and been fine. I’m not wishing for a cat to die in my wall.
I don’t believe in ghosts, which is okay because they probably don’t believe in me either.
That said, if the sound gets louder or you hear a menacing voice saying “GET…OUT…” – well, don’t be a hero. 
Just scream a bunch of scary latin sounding gibberish at it. Like “dominis exos exidos,” and do the sign of the cross with holy water in a squirt gun.
Maybe you’ll get lucky and your attic will chill the frick out, since you’ve out-weirded it.
All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy. All work and no play make Jack a dull boy.
Game Over!
Zebra wins!
Given “horse + typewriter” I was going to go with “Secretariat.”