A method for calibrating a speakerphone system under test is provided herein, comprising: connecting a calibration unit to the speakerphone system under test (SSUT) via a communications interface, and wherein the SSUT further comprises a loudspeaker, microphone (mic), and mechanical vibration sensor (MVS); generating a first test signal by the calibration unit and transmitting the same to the SSUT; generating a first set of mechanical vibrations in response to the first test signal in the SSUT; and determining a calibration factor in regard to the first test signal and first set of mechanical vibrations by the calibration unit.