Does this happen on all the jacks???
You have the latest drivers from Realtek site??
Might try to get rid of any electronics that are near the computer or plugged into the same outlet, experiment. Even an outlet on the same breaker may introduce interference. Same with other headphones/speakers.
I had to buy a line filter to put between the stereo and tv after hooking something up, can't remember??? Not even sure if it is between stereo and tv. Might be computer and stereo? If you are getting it in the headphones it will not help much, as my problem was a low hum produced by something.
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