I'd check if the installer (person) accidentally put in too many motherboard standoff studs.
If that doesn't clear it up, install a sound card. Cheaper than a motherboard.
My pc recently switched cases and ever since then the jacks haven’t worked . If my volume is on full I can hear very very almost unherable sounds that I want to hear . But I can hear lots of high pitched static noise . I am using Windows 7 and Realtek hd audio manager .
Thanks for any help !

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