The reset procedure has nothing to do with the program's functionality. Try looking in the Recording section of the Audio properties to see if the StereoMix is available and enabled.
This is how it looks like:
No program will record sound coming from your speakers or the audio card is that virtual device is disabled. If you can't find the Stereo Mix in the Recording list, right click it and choose Show Disabled/Disconnected devices.
Additionally, you might have to install the latest drivers for your sound card to be able to see and enable Stereo Mix.