I have tried everything, and I can't see anything in the audio software which comes with Windows 10 that is not right.
The problem is the left ear is very, very quiet, and the right ear is okay. Here's the thing though. I have a mixer, and it has a USB connection to the computer for input from the mixer and output from the PC into the mixer. It's a two way street on the USB between both units. When I open my PC audio software settings, and I choose the CODEC speaker output for my mixer, the audio is perfect. It's really great.
So basically audio out of the USB jack on the PC is good, but audio out of the speaker jack on the PC is wobbly.
Any advice on this sort of thing?