The strange noises one hears when a computer is connecting to a network or when you pick up the phone while your computer is connected on the same line. You'll hear a bunch of strange-sounding, rubber-band-like boinging noises. Baud barf also refers to the garbage one sees on the display screen when the modem connection has an incorrect protocol setting. Baud barf is not completely random; hackers with serial-line experience can usually tell whether the device at the other end is expecting a higher or lower speed than that in which the terminal is set, and extremely experienced hackers can identify particular speeds.
NetLingo Classification: Online Jargon