They hear it in Windsor, Ontario across the river from Detroit too ...
Canada to Study Mysterious ‘Windsor Hum’
“Some people have described the sound as a low, humming drone. Others say it changes into a heavy “whump, whump, whump” sound. Still others have compared it to the bass rumblings of soul singer Barry White.”
http://www.livescience.com/26491-windsor-hum.html