Have you heard 'the Hum'?

It's been described as "an anomalous sound heard around the world", a low frequency noise documented by thousands of people, including hundreds of reported cases here in NZ, since it was first identified in the 1970s. So have you ever heard 'the Hum'? Finding a legitimate source or logical explanation hasn't been easy; scientific studies so far are sketchy and people who don't hear it tend to dismiss it as tinnitus, or some kind of modern mass delusion, but for sufferers it's very real, affecting their sleep, and in some cases profoundly altering their lives, jobs and relationships. Colin Dickey wrote about the Hum for The New Republic and his book about haunted houses, Ghostland, comes out in October.