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To me, it sounded like birds chirping into a very low-quality microphone.



Then, it sounded like a very distant fire alarm.

Actually its a good microphone. The audio was originally recorded in 24 Bit 96khz quality. Its just YouTube and other services compressed it to the point of sounding like crap.
 
It's a building fire alarm.

Could've been set off by any number of things.

If you'd have looked at the building the sound was coming from, even from the outside, you'd have seen the strobes going off.
 
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