How to remove outlet noise

I have four Audio Prism "Quietline" plugged into various outlets around my house. i have two on the circuit that my equipment is plugged into and one on each of the other house circuits. They seem to work fine.

Or you can try the Blue Circle Noisehound for cheap. Plug it to the outlet that's making the noise and it'll go away.

Yeah, try a Noisehound...

If you have a cable TV line near the wall plug unplug it and see if the noise goes away. You may also try grounding the cable line.

If you have t12 fluorescent lights with magnetic ballasts on the same circuit the will also inject noise in the line. Try converting to T8 with electronic ballast.

I have found using a Monster AV2000 gets rid of noise in the lines.

Get an isolation transformer type of line conditioner like PowerVar or OneAc type. You should get at least 12Amp rated. There should be plenty on the used market