My Computer Monitor produces a lot of line noise when recording through a mic or an accoustic guitar pickup. By moving around and aiming the mic/guitar in different directions I can greatly reduce the noise that is picked up but not eliminate it totally. And If I turn the monitor off, I have a very clean, noise free sound. I'm in a very cramped space (the forward cabin of a sailboat) and so just getting far enough away from the computer monitor is not the answer. Anybody know of any great filter/device for addressing this type of noise? Thanks!