I use a pair of Fostex PM 0.5s connected to a PM 0.5 sub which I then have connected to a mini Behringer PA mixer, I have an Edirol UA-25 audio interface connected to one input and a DJ setup connected to the other input on the mixer, all connections are made using balanced cables. Recently I added a Dell computer display to my set up but whenever I turn on the computer monitor I get a set volume buzzing sound. This only happens when the computer screen is on. Does anyone have any solutions to try?