If you must work in rain or snow in the field, moisture can be sealed out of audio connectors by tightly wrapping them with plastic electrical tape. It should be emphasized that this applies to mic cables only. If power cords are used in the field for the camera, lights, or recorder, these cables and connectors must always be kept dry to avoid a dangerous electrical shock hazard. Positioning Mic Cables R unning mic cables parallel to power cords often creates hum and interference problems. The solution is often as simple as moving a mic cable a meter away from any power cord.
Fluorescent lights can also induce an annoying buzz in audio.
Computers and certain types of medical equipment, especially if they are near audio cables or equipment, can also create undesirable noise. By carefully listening to your audio pickup with a set of high-quality, padded earphones, you can generally catch these problems before it's too late.