I've got Sony Bluetooth earbuds a few years back and I guess they have something called "multipoint" where they can connect to multiple devices at once. I had to Google why anyone would want that, but I guess it's to make switching between devices faster.

Sometimes I'll be walking down the sidewalk with my earbuds in, connected to the phone in my pocket, and they'll just randomly make the sound it makes when connecting or disconnecting. Like I'm connecting to the BT of a random house or business I walked past that I never explicitly paired with.

I can't exactly put my finger on why, but I find it very unsettling every single time and wish I could turn that feature off.