I get a "flatline" when I record on Audacity

Dear Forum,
Help!
I have installed Audacity on both my Desktop and my Laptop computers. I have WINDOWS 10 on both computers and Audacity 2.x.x.
Until yesterday, it worked perfectly on both computers.
But now, I can only record on my laptop.
The desktop only shows a “flat line” where, before, the waveforms showed and worked perfectly on both.
I’ve been using a Yeti Blue Microphone and a Sony headset and, again, both worked perfectly on both computers.
At first, I thought it might be a cable issue but the cable works on the laptop.
I uninstalled and re-installed Audacity on the desktop thinking that Audacity might have been the issue but it still does not record.
After hours of comparing the Audacity screens on both computers, I found that the “recording volume” tool shows a recording level of “1” on the laptop and “0” on the desktop.
I cannot get the recording volume to move off the “0.” Even when I manually change to “1,” it jumps back to “0.”
What can I do to get it recording again?
Thanks,
Bob

I’ve been using a Yeti Blue Microphone and a Sony headset and, again, both worked perfectly on both computers.

Make sure you’ve selected the correct [u]Recording Device[/u]. The Yeti might not say “Yeti”, but it should say “USB…something”.

If the headset is also USB the driver might be “confused” after plugging them both in, but one of them should work.

Thanks for the quick response.
It looks like a faulty cable and, with it being changed, Audacity works perfectly again.
Much Appreciated.
Bob