Abstract: A method and apparatus is provided for performing longitudinal balance calibration. A differential signal is provided. A calibration of a gain of at least a portion of the differential signal to affect the longitudinal balance associated with the differential signal. Performing the calibration includes: receiving a first portion of the differential signal and determining a gain associated with the first portion; receiving a second portion of the differential signal and determining a gain associated with the second portion; determining a difference between the respective gains of the first and second portions to determine whether the difference is outside a predetermined range of tolerance; and modifying at least of the gain of the first portion and the gain of the second portion based upon a determination that the difference is outside the predetermined range of tolerance.