PURPOSE:To eliminate the noises which are generated immediately before the stoppage or at the start of a tape driving motor with a simple constitution, by applying muting immediately to a sound recording/reproducing circuit after a pause switch is turned on. CONSTITUTION:A capacitor C is immediately charged after a pause switch 2 is applied to the ON side, and a muting transistor (TR) is turned on. Therefore both the sound recording and reproducing outputs emerging at the output terminal of a sound recording/reproducing circuit 3 are earthed by the TR and never transmitted to the following stage. This prevents that the noises are produced or the sound recording is carried out in an abnormal state while a motor 1 is revolved by inertia. Under such conditions, the switch 2 is applied to the OFF side to release the pause state. Thus the electric charge stored to the capacitor C is discharged via a resistance R, and the TR releases the muting state after a fixed period of time. Therefore it is completely prevented that the output of the circuit 3 is transmitted to the following stage before the motor 1 is revolved at a normal speed.