Shot a dance team demo in a standard high school gymnasium. Like most gyms the lighting emitted an annoying sound that detracts from the video. Is there an audio filter or combination of filters in FCP that could effectively lessen this noise but not completely "squash" the on-location audio?
Lighting buzz is rarely a single frequency.so simple EQ filtering will not solve the problem. To find out, try a parametric notch EQ, make the notch as small as possible (increase the Q value), add gain and then sweep the frequency up and down until you hear a jump in the gain of the buzz. By reducing gain at this frequency you will hear if it solves the problem.
An anternate approach is to use noise reduction software. Sound Track Pro has a de-noiser. Waves, Isotope, CEDAR are other brands of de-noising & de-buzzing software.