What I will say here is absolutely genuine and I have no reason to lie and make up any stories. You must also know, that I'm not even a believer, but atheist, however I clearly can't explain this phenomena what I experienced when I was a kid:
In 90's, the place where I live was facing serious econimical crisis and we didn't even have simple electricity for whole day. I grew up mostly on candles. I remember that few times, in the morning (or at night, can't exactly recall exact time) when everyone was sleeping, I was hearing very weird singing. It wasn't even a song, but a choir of multiple voices, it was like how to say, overtones (don't even know if it's a right word to describe). After so many years, I still remember this choir or whatever it was. When this happened, everyone was sleeping and it was very silent. I felt scary, but didn't wake up anyone. I don't exactly remember if this happened only once or a few times. There is no way neighbors would sing and to be honest it didn't even sound like human choir. I never had any trauma or psychologial problems in my life, I'm a normal person, never even experienced any hallucinations, so I really can't explain this phenomena. Since that, after many hours I never experienced this. As I already stated, I'm not a religious or spiritual person at all, but there is a second phenomena I noticed recently that is hard to ignore: I don't know if it's coincidence or no, but very often I see the numbers 11:11 or 1:11, almost everywhere, whenever I look at the clock or whenever I pause the movie time remaining shows those numbers or even on Microwave... I don't know if those two things are connected to each other, I don't even know what is going on. Maybe those 11:11s are just coincidences (but it's too much for coincidence), but can't really explain the choirs in my childhood.