Fluctuations in input intensity and pulsewidth affect the frequency doubled output pulse of a fiber grating optical pulse compressor in a compressed, continuous-wave, mode-locked Nd:YAG laser system. An optimized intensity servo system greatly reduces these fluctuations and results in as much as 50 dB noise reduction at low frequencies. Fluctuations in either input intensity or pulsewidth are corrected by changing the input intensity by means of the servo system.