Apparently it's been a thing:
http://nyeveningnews.com/2018/06/14/hundreds-of-people-shaken-after-another-mysterious-boom-sound-rocks-pennsylvania/
https://kmbz.radio.com/articles/pennsylvania-authorities-discover-source-mysterious-booms-middle-night
https://thedailycoin.org/2018/06/01/unexplained-booms-mysterious-sounds-what-are-they/
http://www.foxnews.com/us/2018/05/30/mysterious-explosions-plague-pennsylvania-towns-straining-emergency-services-police-say.html