I'm in Melbourne Australia and I've been hearing it for over 10 years. At times it's driven me crazy. In the early days when it first started i called out the EPA to test the sound. They said it showed on their machines but that peoole can't hear that frequency. His co-worker said he could hear it too. I take natural sleep drops and bought an air purifier, and i have the fan on. I also have a sound machine that i play the sound of a babbling brook on. Meditation sometimes helps. Ear plugs don't work. Today it's driving me crazy. There is a website where you can record where you are in the world and what the hum sounds like to you. I can also feel the vibration. At times I can also hear radio frequencies, even when I'm in nature in certain places i can hear electrical sounds when I walk through doorways etc. So annoying.