XoneK2 does unbearable high pitched noise when plugging in or when lights are on

Hi

Only on the bottom headphone out I get a high pitch noise.

It happens for a few seconds when I plug the unit in, it’s so loud I have to take my headphones off. Does not seem to happen on the RCA out. Happens with different computers, headphones and USB cables. During use it’s almost gone when LEDs are off. And louder depending on how many lights are on.