Videomaker – Learn video production and editing, camera reviews › Forums › Technique › Sound › Get rid of high hum in background › That’s not “hum” but “hiss
That’s not “hum” but “hiss.” “Hum” s a lower-frequency constant noise, one with some pitch to it (almost like a musical note). “Hiss” is the high-frequency “white noise” you have (you’ll find it in between FM stations, for example). It plagued cassette recordings which is why Dolby was used as a way to reduce that background hiss. It’s best to reduce it on the way in, if you can, if not, I agree with others that it may be possible to strip it out using software.