noise in monitors from main output

I'm having trouble installing MPCX and coordinating with MPC Software. MPC Software has been loaded onto the computer, hardware is in "Controller mode" and there is of course a USB connection. As an audio device I chose Akai Pro MPCX Asio, Active Output Channels: Out 1 + 2 and Out 3 + 4. I also updated MPCX to the latest version. Everything should therefore work perfectly fine. However, in monitors connected to the MPCX (main output) and in the headphones, you can hear a terrible noise (like on the old FM radio). The noise disappears when I unplug the USB cable. What's happening? How to fix it?

Maybe ground loop, are you on the same power outlet for both mpc and the pc? (if not try that) also a power conditioner is a useful item to have in a home studio. My assumption here is you have your mpc and pc on different plugs and you got a weird ground loop going on but dont quote me, just worth lookin into.

My guess is ground loop as well.

mpc and the pc are on different power outlets...

Ultros wrote:Maybe ground loop, are you on the same power outlet for both mpc and the pc? (if not try that) also a power conditioner is a useful item to have in a home studio. My assumption here is you have your mpc and pc on different plugs and you got a weird ground loop going on but dont quote me, just worth lookin into.

you were right, thanks

ok, problem solved, it was a hum from a laptop AC power, thanks for help, regards

Rock on!