Ground noise

In electronics, ground noise is electronic noise on the ground wires or busses of an electronic circuit. In audio, radio, and digital equipment it represents an undesirable condition since the noise can get into the signal path of the device, appearing as interference in the output. Like other types of electronic noise it can manifest in audio equipment as a hum, hiss, distortion or other unwanted sound in the speakers, in analog video equipment as "snow" on the screen, and in digital circuits and control systems as erratic or faulty operation or computer "crashes". A major source of ground noise is ground loops created by improper interconnection of audio, video or computer components.