It's to do with disabling Line Out, Record or one of the other mixer tabs - it's so long ago since I configured one that I can't remember.
I don't have a mic at present so can't actually check, especially as I've since switched from 98SE to XP...:-(
OnePlus 5 review
Alice Saey's mesmerising animation for Dutch singer Mark Lotterman
iPad Pro 10.5in (2017) review
Comment faire une capture d’écran sur un Mac ?