Windows 10 audio problems with fldigi and the fix
In updating to Windows 10, some folks have had a problem with fldigi audio.
Their computer does not recognize any sound device when they are setting up the audio for fldigi. To confuse matters, other sound card programs may work as usual.
This is not universal, many people make the upgrade with no problem at all. But since you are here, you likely are having a problem.
To cure this there are a couple steps to try, in this order.
First, try right clicking on your speaker icon in your task bar and select “Troubleshoot sound problems. This has fixed the problem for some folks, but a many still have the problem afterwards. It’s still worth a try.
Even if you are told you have valid sound card driver by W10 yet it still doesn't fix the problem, go to your internal sound card producer’s site, and check for the latest driver.
There's a very good chance the latest driver for the sound card on your computer is actually not the latest. You then download and install the new driver. The problem should be fixed now.
Note1: Even if you are using an outboard device, replacing the internal sound card driver usually fixes the problem.
Note2: This problem is probably in the way the portaudio library checks for audio devices. If it runs through it’s check and the first on it hits - the motherboard, has a bad driver, it thinks there are no applicable drivers on the computer.