Do you have option to connect monitor/TV via HDMI and to disable onboard audio? This could resolve if it is onboard audio problem or something else.
Have you tried full removal of drivers and clean install again?
P.S. had that problem when I was noob 10 years ago with recording. Plugged in my Guitar AMP im MIC jack and burned sound card
. Got that silly noises and half jacks would not work.