DFW
I love a good mystery, so I confess I love this thread. I agree with others — in my contact with local law enforcement through Blockwatch groups and such, they emphasized that this is what they are there for. They WANT you to call. Just give them a tip, let them know even if you feel silly about it, but also that it’s unsettling enough that it’s been bothering you. They will respond and they won’t identify you.
I would love an update on how this turned out — without identifying anyone, of course, as it could be totally mundane. We actually have a couple air compressors in our garage that occasionally switch on when no one is in there — they are set to automatically regulate their air pressure, so they’ll turn on to regulate every once in awhile. I’m sure it sounds very weird to our neighbors, too (though nothing like you are describing).
Good luck!
Sincerely,
Mrs. Kravitz