you might have a bad ground that is being fed back as static through your sound card,,
check the grounding on the case and the outlet/power bar that you use for wire breaks , etc..
It could also be a bad component on one of your cards,, video, sound, Nic, Modem ..
anything getting power,, that is starting to go,, the resonating happening in the possible "dying" part,, will begin to Whine as the frequency becomes more established,, as the whine increases(in pitch),, be prepared for failure,,,,
Just some possibles on WEIRD noises
MCSE, MCP+I, A+
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