I sought help from the "Your Place" community, and, as the column made its way from Philadelphia to newspapers across the country, I received more e-mails offering solutions than I could count.
Chuck Coburn. "I have several battery-operated devices in my house, foremost is my smoke/CO/flammable gas detectors. When one of these devices' battery gives out, a sound is made. . . . Perhaps one is malfunctioning."
Rich Madara: "I'd be willing to bet the noise is louder in the room where the lines are attached to the house. Have been on trouble calls for exactly the same symptoms, found that the phone or cable lines were strung too tight with wind vibrating them harmonically, or there could be a small tree limb on the lines moving like a bow on a violin making the hum."
Pat Drago: "Many years ago we had a similar humming noise, which after much investigation turned out to be the result of hornets making their way into the wall of my living room through a small hole in the caulking between the siding and chimney. They had built an enormous nest inside the wall."
Mary Dudar: "We had the same scenario that was the motor on the neighbor's radon system. The motor created a vibration that traveled underground to our house."
Ruth Speary: "A humming sound was waking me up . . . and driving me crazy. I contacted our electric company and asked if it could be a transformer near our property. They traced the source . . . to the pollution control device on the roof of a plant a few miles away."
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