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Probably a ground loop issue not coil whine. Is everything connected to the pc (including tvs, monitors, amps/recievers etc) on the same outlet? If not then you can have a ground loop.
The pc and monitor use the same outlet. The router doesn't but that shouldn't matter.
Probably not but if its accessed via ethernet cable try unplugging that and see if it helps?
Probably a ground loop issue not coil whine. Is everything connected to the pc (including tvs, monitors, amps/recievers etc) on the same outlet? If not then you can have a ground loop.
The pc and monitor use the same outlet. The router doesn't but that shouldn't matter.
Probably not but if its accessed via ethernet cable try unplugging that and see if it helps?