A system for diminishing differential harmonics of common resonance tracking modulation in a resonant fiber optic gyroscope, RFOG,, comprising: beat note servo (180, 280) circuitry configured to receive an electrical beat note signal and to generate at least one differential harmonic alternating current, AC, error signal, where the at least one differential harmonic AC error signal is generated using the electrical beat note signal, where the electrical beat note signal is created from a beat note of a first optical signal generated by a first optical laser and a second optical signal generated by a second laser, where the first optical signal and the second optical signal are modulated with the common resonance tracking modulation, where the first optical signal circulates in a first direction in a resonator of the RFOG, and where the second optical signal circulates in a second direction in the resonator of the RFOG that is opposite the first direction; differential harmonic correction circuitry (182, 382) configured to generate at least one error cancellation signal, where each error cancellation signal is generated using a corresponding differential harmonic AC error signal, and where each error cancellation signal and its corresponding differential harmonic AC error signal correspond to a differential harmonic desired to be diminished; and adder circuitry configured to add the at least one error cancellation signal to an offset frequency signal to the differential harmonics, where the offset frequency signal comprises a frequency used to tune a carrier frequency of one of the first optical signal and the second optical signal to a resonant frequency in respectively one of the first direction and the second direction; wherein each differential harmonic of the common resonance tracking modulation is a vectoral difference between a harmonic of the common resonance tracking modulation of the first optical signal and a same harmonic of the common resonance tracking modulation of the second optical signal, and where a harmonic may be a fundamental frequency. beat note servo (180, 280) circuitry configured to receive an electrical beat note signal and to generate at least one differential harmonic alternating current, AC, error signal, where the at least one differential harmonic AC error signal is generated using the electrical beat note signal, where the electrical beat note signal is created from a beat note of a first optical signal generated by a first optical laser and a second optical signal generated by a second laser, where the first optical signal and the second optical signal are modulated with the common resonance tracking modulation, where the first optical signal circulates in a first direction in a resonator of the RFOG, and where the second optical signal circulates in a second direction in the resonator of the RFOG that is opposite the first direction; differential harmonic correction circuitry (182, 382) configured to generate at least one error cancellation signal, where each error cancellation signal is generated using a corresponding differential harmonic AC error signal, and where each error cancellation signal and its corresponding differential harmonic AC error signal correspond to a differential harmonic desired to be diminished; and adder circuitry configured to add the at least one error cancellation signal to an offset frequency signal to the differential harmonics, where the offset frequency signal comprises a frequency used to tune a carrier frequency of one of the first optical signal and the second optical signal to a resonant frequency in respectively one of the first direction and the second direction; wherein each differential harmonic of the common resonance tracking modulation is a vectoral difference between a harmonic of the common resonance tracking modulation of the first optical signal and a same harmonic of the common resonance tracking modulation of the second optical signal, and where a harmonic may be a fundamental frequency.