Hello, new to the board, swung by when i noticed you guys are pretty good at answering tech questions... my issue here is my setup has been flawless until i recently added a DJ Mixer to it. I used to have my speaker monitors (basically powerful speakers with their own power supply) set up directly to my sound card to play everything from my computer. Then I had an external Monitor to run a dual monitor set-up. I recently purchased turn tables so I picked up the mixer so I could have two channels for the tables, 1 channel for my record player and another for my computer. The new set-up was working perfectly until I tried plugging in my external monitor again. As soon as it was plugged in a high pitch frequency came along with it. I checked all the inputs and it is certainly coming from the mixer, the buzzing only gets louder when the mixer volume is turned up, and doesn't change when any of the channel volumes are adjusted. I also tried separating the power supplies for the monitors and the computer monitors and moving the plugs so they're not on the same powerbar, but I'm still not getting any solution. Can anyone help me out? I realize proximity between the monitors, computer monitor and mixer maybe be an issue, and I've been trying to move some stuff around but with limited wire length it's been a little hectic. Please help a sound guy in need.