I noticed that many people in these forums ask for additional information using something like speccy. Please see this information below, where it will hopefully provide more information to help solve this problem. Thanks!
http://speccy.piriform.com/results/SMIzkWyfHULOcL8VXkRI6gq
I just purchased a used Dell 390, on which I installed a new copy of Windows 10. After setting things up (running windows update, updating drivers, installing necessary programs, etc), I plugged my headphones into the sole headphone jack and found a constant static/buzzing noise.
The noise occurs both when no sound should be playing and when sound/music is playing. The volume on this static is fixed - when I change the volume (or even mute it), the static noise remains unchanged in its own volume. The sound is constant, I have not found anything that increases, decreases, or causes the noise to end.
I have experienced the static noises on two separate headphones (different headphone models as well). I have no microphone plugged in, and my headphones do not include microphones.
I have double checked all relevant drivers I could think of to confirm that they are up to date (all sound drivers). However, the fact that the sound occurs even when muted makes me wonder if it is even an audio issue or not, but I am unsure what else might cause the issue. I have searched around for someone with similar issues, but my googlefu isn't strong enough to have found a solution.
Any suggestions of what to try are appreciated, and I'm happy to provide more information that is relevant to the problem - thanks!

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