feedback during recording

I have been away from Audacity for years, but am back with a question I cannot answer.
The basics - a new HP laptop, Audacity 2.4.1 and the source is Youtube.

But when I hit the “record” button, there is a very, very loud feedback/oscillation which drowns out the actual music I want.

I have tried all possible variations of settings (and cussing) but nothing seems to work. I feel intuitively that the solution is easy and maybe even obvious to others - but I give up, and hope someone can enlighten me and fix this issue.

by the way, since feedback is involved I tried sticking a wad of gum over the microphone hole, but that did nothing.

Thanks in advance for your help
Felix (I hate computers, and they hate me)

Make sure [u]Software Playthrough[/u] is turned off (it can create an internal feedback loop).

Thanks - that did the trick.