I dunno. My husband and I have heard a humming at some points, but reading some of these texts, I do have to wonder if many of you actually have tinnitus, which seems to have become very common over the past few years. Maybe it's related to all the electronics, especially the cell phone/wifi technology. I have tinnitus myself and can tell you, it can be maddening at times. It's best to regulate diet and sleep, use white noise and try to ignore it as much as possible.