Troubleshooting Noise on a Home Phone Lineby Keith Evans
Verify Secure Connections at the Telephone
Noise, like static, on a home telephone line may be caused by a number of factors. To begin troubleshooting, first verify whether the noise is on one or all telephones. If the noise can be heard on only one telephone, check the wire connecting the telephone set to the wall jack; this modular wire is designed to be easily removed from both the phone and the jack, and can be easily swapped out with another wire from a nearby telephone. The thicker wire connecting the phone and the handset, affectionately known in the telecommunications industry as the "curly cord," is similarly designed to be easily swapped out. If replacing either of these wires resolves the issue, replacement wires are readily available at most electronics and discount chain stores.
Check Connections at the NID
If the noise is present at two or more phones in the home, the trouble may be a loose connection at the network interface device, known in telecommunications circles as the NID. This device resembles a small plastic box mounted to the outside of the home. It may be held closed by a screw or plastic clips. Open the NID and verify that all wires are securely connected. If any wires seem loose, remove and reset all wires, starting with the red and green wires, then optionally continuing to the yellow and black wires. If the inside of the NID appears to be damp or wet, carefully dry all wire connections and notify the telephone company of a leaking NID.
Test the NID
After verifying secure connections for all wires inside the NID, test the telephone network connection by plugging a phone directly into the network interface. Inside, the NID should feature two standard RJ-11 modular telephone jacks; one or both may appear to be in use. To test the line, unplug the plastic modular plug from the port that appears to be in us, and plug a working telephone into the jack. If no static or noise is heard, the trouble is likely isolated to somewhere inside the house and a professional evaluation may be in order.
For More Complex Issues, Contact the Telephone Company
If noise persists on the telephone line after verifying individual telephone connections and testing the NID, the trouble may be in the telephone network. For more advanced troubleshooting, or to have inside wiring tested, consult the local telephone company's repair department by calling the local business office or dialing "6-1-1" from a working telephone. Some telephone companies offer insurance that covers repair of telephone wiring inside the home, though resilient inside wiring is rarely the cause of telephone line noise.