The authors studied the effect on microphone potentials of one-minute mechanical manipulation of the conductive apparatus without damage to the stapes and opening of the vestibulum in guinea pigs. A decrease in microphone potentials with a subsequent slow restitution to the initial values was observed. The results of the mechanical manipulation were compared with the effect of white noise, intensity 120 dB. After one-minute manipulation, the decrease in the amplitude of microphone potentials and their restitution simulate the course of changes in microphone potentials after 5-minute deafening with white noise.