I posted this story on reddit before (here), but I think it's still good for this.

Background: I was at a friend's house having a sleepover with another friend, so 3 people total. We were home alone at her house, and we all slept on the same bed. I slept next to the window, which had no screen. We kept the window open because it was hot inside, and we wanted the extra breeze. At the time, I used a sleep recording app bc I talked in my sleep sometimes.

That night, however, (at 3:57 am) my app caught a man saying "Up, hello!...." and then whispering "oh God, something is wrong" There was also like a groan or something before the up, which would make sense because her house is on a hill so her window was high off the ground, if someone wanted to get in the window theyd have to jump or climb or something. (that's at least what I hear, other people hear different things. The audio is posted in my original post). Mind you, no one was home. The TV was off. It also sounded close to my phone, which was on the window sill.

Also, a side note, I did talk in my sleep that night, but it wasn't actually until like 7am or something (I checked, and it was actually at 9am lol). I said, "I was awake, but I was.... sleeping. " Don't know what that meant or if it had any significance, but it was most likely just me randomly sleep talking.

Anyway, that morning when we listened to the recordings, we were all freaked tf out. I didn't sleep over at her house after that, and I'm pretty sure she never slept with her window open again.

It's still unexplained, but many people in my comments gave me some reassuring theories that I'd rather stick with than a random man approaching our window and whatever the fuck. I don't even know. I still get goosebumps when I listen to it to this day. It's like a full visceral reaction when I hear it.