My gag was a bird chirp that would play every so often--typically minutes between chirps. There were several random numbers that went into making the chirp so

My gag was a bird chirp that would play every so often--typically minutes between chirps. There were several random numbers that went into making the chirp so it would be different every time and every noise it made would be shifting frequency, never a moment of a fixed tone (back when speakers usually just went BEEP.) Leave it running on a machine that wasn't being used...