The answer is Crosstalk as this phenomenon is most commonly associated with analog phone call.
Now, crosstalk is defined as a disturbance caused by the electric or magnetic fields of one telecommunication signal which affects a signal in an adjacent circuit. In a telephone circuit, crosstalk could result in hearing part of a voice conversation from another circuit. Hence, the phenomenon that causes crosstalk is called electromagnetic interference (EMI). This may occur in microcircuits within computers and audio equipments including within network circuits. This term is also usually applied to optical signals that interfere with each other.
