Apple AirPort Express 802.11n (1st Generation) - Manual (Page 36)

36 Chapter 4 Tips and Troubleshooting
Items That Can Cause Interference with AirPort
The farther away the interference source, the less likely it is to cause a problem. The
following items can cause interference with AirPort communication:
 Microwave ovens
 Direct Satellite Service (DSS) radio frequency leakage
 The original coaxial cable that came with certain types of satellite dishes. Contact the
device manufacturer and obtain newer cables.
 Certain electrical devices such as power lines, electrical railroad tracks, and power
stations
 Cordless telephones that operate in the 2.4 GHz range. If you have problems with
your phone or AirPort communication, change the channel your base station or
AirPort Express uses.
 Adjacent base stations using nearby channels. For example, if base station A is set to
channel 1, base station B should be set to channel 4 or higher.