Windows 11 does not record in stereo from a USB turntable

I was able to figure it out:

I use a Xenyx 302USB audio interface to record a radio program. Anyway. I was having the same issue - "mono" identical recordings on both left and right channels despite the audio output on my monitor speakers being correct.

In Windows 11:

Right click on the sound icon in the system tray

Select Sound Settings

Scroll down to Input

Click on the right arrow next to the "microphone" that is designated as your USB audio interface

Under Input Settings, Format select the dropdown arrow and choose an appropriate stereo option - mine was defaulted to a mono option for some reason.

My Operations Manager at the radio station let me know that my last three recordings have been mono and I couldn't for the life of me figure out why. It started when I switched to Windows 11...

I have recorded hundreds of (stereo) records on Audacity using an Audio-Technica turntable connected to a Windows 10 laptop via USB. When I purchased a new laptop with Windows 11, I could no longer record in stereo. (Both channels show recording, but it's only recording one channel twice.) I have tried all the remedies here and elsewhere on the internet; I have followed the latest Audacity (3.1.3) instructions (which evidently haven't been upgraded for Windows 11); I have made sure that everything is set the same as on the old computer, at least to the extent possible--as Windows 11 sound settings are different . . . but nothing works.

Fortunately, this Dell laptop's microphone plugin can be set to "input"--which allows me to use a cable with RCA connectors to a 1/2" plug and record in stereo. It is not as handy as using USB, but that is the only way I have found to record stereo as of now. Unfortunately, I cannot use headphones at the same time I record.

You mentioned one step out of dozens given before rejecting my post which I spent quite a while researching for you.

This is an interactive process. I give steps to perform, you do each one and then report back results until something works, so I know what to suggest next. If you need help performing any step, just ask back. But please do not skip any steps. We often find out the skipped step is the fix.

As you can see, these (left and right) channels are identical. I get the same results on Win 11--not true stereo, just one of the stereo channels recording on both left and right.

I had no problem with the turntable. In fact, I've installed it on other PCs which are able to record both stereo channels. However, on my main laptop (and only on that laptop), I get the same signal for both stereo channels. I also have a cassette player which I use as an audio input. It also works on my Windows 10 laptop but it has the same stereo problem on my Windows 11 laptop. There's obviously some setting that's wrong on my Windows 11 PC, but I don't know what it could be. I've tried turning Stereo Mix on and off, uninstalling and reinstalling USB ports, updating my system and audio card drivers, and everything else in the post above.

Thanks!