Cool new development

I'm in the bathroom and from what is probably a window to an air shaft in the middle of the building I hear a person yelling, screaming (but sounding far away, as if trapped somewhere) "I DONT WANNA DIE HERE! SOMEBODY HELP ME!....." I get up close, stick my ear to the window. Mumbles, incoherent screaming, " WHY CANT I GO TO THE TOILET!?" And shit like that. Nice! The window is painted shut. I put my ear up to it again, and don't hear anything. I sit with my ear pasted to the window, then, "WHY ISNT ANYONE HEARING ME? IM TRAPPED! IM GOING TO DIE HERE!" Sounds muffled and like the person is terrified also, or...dying.
I finally bust the window open, there is an air shaft there, and I'm at the bottom. I hear it louder "HELLLLLLPPPPP MEEEEEE BLOOOOOOODDDD MUMBLE MUMBLE AGHHHHHH!" I can't tell if it's coming from above or below, but it sounds so far away and muffled, like this person is in a mainly-sound-proofed room. Oh god, I watch too much x-files, I'm going crazy.
I'm on the first floor with an air shaft and downstairs there's a horrifying room off the trash room with like 8 locks on it in the basement, sounds like it's coming from there. I can still tell the person is hoarse from screaming, it sounds like they've been screaming for days. I go wake up my sister and her boyfriend who are in town. Mark says he heard it yesterday too, sounded like a woman screaming for help. WEIRD HE DIDNT SAY ANYTHING!?! I go back in. I'm too scared to reply. "Hellllooo?" I half whisper, half yell. When I finally get up courage I yell 'Shaft ghost??" into it, I get no answer. It stops completely.
I already called the maintenance guy and left a message asking if someone was being tortured in the basement. "I'm not crazy, I'm not crazy, but they're yelling HELP ME I DONT WANNA DIE HERE!" When he finally calls back, "oh it's just the schizophrenic guy! On the fourth floor. He has outbursts"
Of course it is! No shaft ghost...?
God bless the Tenderloin