The first thing to do when troubleshooting static is to methodically disconnect each piece of equipment that is connected to your phone line. This includes other phones, answering machines, DSL modems, fax machines, computers connected via dial-up, and alarm systems.
 Each time you disconnect a piece of equipment, listen for static on the line. If the static stops, then the last piece you disconnected is likely causing the interference.


Try plugging the offending piece of equipment into a different jack if possible.
 It's possible the jack itself is causing the interference, and not the device that was connected. If the static returns after plugging in a different phone or device, you'll need to replace the jack. See Install a Residential Telephone Jack for instructions.
 If you're experiencing static or other interference on your cordless phone, there may be too many signals on the frequency. Look for a Channel button on your handset or on the base station. Change channels until you find one clear of interference.
 Certain electronics impede on the frequency used by cordless phones, and moving or turning off this equipment may help your signal.Try to keep cordless phones out of your kitchen, as microwave ovens will often disrupt the signal.
Home wireless networks running on 802.11b/g are operating on the same frequency as your cordless phone (2.4GHz. You may need to upgrade your router to one that supports 5GHz wireless. See Choose a Wireless Router for more information.
Baby monitors, bluetooth devices, and other cordless phones can all cause interference.
Disconnect telephone equipment one at a time while listening on the phone.
Listen for the static to go away.
Test the offending jack by plugging in a different phone or device.
Try changing channels on your cordless phones.
Move or disable interfering equipment.
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