To disable internet I would
Go to Control Panel
Click Network & Sharing
Click Change Adapter settings (which displays all network adapters)

Right click any active one and select Disable
After testing you could simply right-click and Enable to return.

Have you yet eliminated the USB cable?
I'm telling you, as a guy who works with PCs every day, I was surprised that one thing fixed issues that I had been 'fishing' for a week or so with lots of frustration.

I'm not saying it is the answer for sure, but it was a surprise to me when all the issues went away with the new cable.
My problems appeared random like yours and I was convinced it was system related .. but it wasn't in my case.
Just trying to help and you can feel free to blame me if it doesn't work.

I do not work here, but the benefits are still awesome
Make your sound your own!