My partner is pretty much a skeptic when it comes to other people's stories of strange phenomenon. But he has one story about something he could not figure out and to this day wonders what happened. He thinks there is a rational explanation for most everything that people 'experience', but even he could not find one for what happened to him before we met.
He lived in a tiny 2 bedroom house with his ex girlfriend (Ive been to that house, and he told me the story while he was still living there, so I know the house and room layout and spent almost a year there visiting him before we moved in together). Anyway, so he and his ex were sleeping in bed one night and he woke up hearing women's voices. More like one woman's voice was clear, and others were muffled. He laid there listening to it for awhile, trying to figure out where it came from. It was chilly out so he didn't have the bedroom window or any other windows open, but the voices were loud enough to seem like they were coming from within his house. He thought 'WTF??', like someone WAS in his house. He listened more and it seemed to be coming from toward his closet, which was right beside the door into the main house. So he slowly quietly got out of bed and headed toward the bedroom door. As he got closer, he expected the sound to change from sounding like it was in his closet to sounding like it was coming from the living room or kitchen or wherever. But it didn't. It sounded more like it was coming from the closet, or rather the floor area, beneath the floor. He stopped and turned around to look back at his ex, and there she was laying in bed with the covers pulled up to her chin - with her eyes bulging WIDE OPEN. Terrified. She could barely speak when she said 'Do you HEAR THAT?'. He shh'd her and crept out of the bedroom. He looked around the house but could not hear the voices coming from there at all. He walked to the top of the stairs to the dirt cellar - nothing! Nothing from the spare bedroom, kitchen, front porch, etc. But he could hear the voices, muffled and far away sounding, like down a tunnel almost - coming from his bedroom. He crept back in and there it was - stronger. He said it was like listening to a group of women having a tea party and chatting away happily, amicably. Just having a lil ole party in his closet. His ex was completely paralyzed with fear in the bed, so he grabbed the closet door and pulled it open - and the voices stopped immediately.
His ex was like 'WTF was that??' and was scared. He looked outside (he did this before opening the closet too, I believe), but it was 4am and he couldnt see anyone anywhere along the street. The neighbour's house was dark, and there are no windows on that side of their house that you might think sound could travel through. They were old people, not prone to being up partying til 4am anyway.
It was just a strange occurrence that he could not explain, scared the crap out of his gf at the time, and never happened again in the several years more that he lived there. You'd think if it was wayward sound traveling through from outside, it would happen at least once more, but it didnt. He was in that house about 10 years and only had that one experience.