HT2494: Mac Basics: Ports and connectorsLearn about Mac Basics: Ports and connectors
Currently Being ModeratedFeb 8, 2013 8:03 AM (in response to Jromeroalva)
Is the noise a humming sound? If so you might be experiencing a ground loop. This happens when two pieces of audio equipment are connected to different grounds (sort of).
You can try making sure both the Mac and amplifier are plugged into the same circuit. You could also try running a wire between the Mac and amp with the wire touching bare metal on both machines, like from one case to the other. Not from anything electrical on either machine.