What could be causing a strange static sounding noise in the headphones only when pressing PFL on any channel.
The "PFL" Stands fo r"Pre Fader Level". Just in case you did not realize. so when you press the "PFL" button , and the red light goes out?, You're saying that the hissing goes away and that you have clarity. Yes? and the volume presents no issues? Also correct? Part of that simply, is with the PFL in the on position. You are engaging the fader for one, which will add to an already boosted signal ( the the fader is turned Up?). also you may have your Clip set incorrectly. to set this you turn PFL off, then at your signal input level Dial (usually at the very top in-line with your fader. _ set the volume on your device, then input clip level on the board \ to where the clip light comes on. not a steady light, but a blinking light so make it steady, then back it off a hair. Okay? this whole time make sure your mains are down. or off at the faders. Once clip is set., PFL is in off position, gradually turn your mains up to level. Now, the PFL is for when you have more than one signal. say from an instrument on another channel. unless you have that? No need to use the PFL. If you do have an instrument in line,. then, before you turn PFL on,make sure that your fader on that channel is turned off. -turn on your PFL, then gradually bring that to level. never messing with the mains level.
I know that is a lot of info. but it is a process. that should eliminate any hissing you may have heard.
Allen & Heath AH...
on Apr 19, 2016