Though not a plauge, this isn't that uncommon an issue. Generally its due to harmonics from video being amplified by your audio card. I've seen this most often (just in the toolset) with folk using a PC with an Intel Video/Audio built into the motherboard itself. It actually happens more than most notice, but the amplified harmonics are usually masked when playing other games, listening to music, etc... . I've one PC that does this, though its just a minor irk and not noticeable when I just listen to a YouTube Playlist as I build
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