Audio Issues: Microphones All Stop Working

Hello. I have a HP Pavillion 500-164 tower. An ancient system, but it has been running Windows 10 just fine. Everything is stock, except for upgraded Memory, PSU, and GPU. No issues after I installed that hardware.

About a week ago, the microphone inputs all stopped working. Playback works fine, any device. My computer has a IDT HD Audio in it. I have tried multiple microphones, front input jack, rear input jack, and even a USB sound card. No difference. The microphones still don't work, no matter which one, where, or what settings I use (Sound Settings).

I recently installed VB- Audio Cable software for some streaming I needed to do. I installed it about a week or two before these problems showed up, so the first thing I did was uninstall VB-Audio Cable. No effect.

Where should I start to trouble shoot this? I have tried all my microphones on another PC and it worked just fine, so I know that isn't the problem. I have tried plugging the USB sound card into different USB ports (that work just fine for every other USB thing I plug in). The USB card was Amazon recommended 4 out of 5 stars customer reviews.

Suggestions please! Thanks!

I have tried uninstalling all the different audio devices and drivers. No luck at all. Any ideas??? This is driving me mad. I'm ready to throw this F*&!^$& computer out the window and buy another one. This is insane!

I just installed a new sound card, and it didn't work either. Any ideas here?