On win 7 i had no audio, and no stereo mix on sound card
settings Video to screen capture, Audio to speakers
then
If you are trying to record sound from streaming video on your computer, you would need to use a stereo mix option (if your sound card supports this). In most cases, you can connect a male to male 3.5mm stereo cable from the speaker output on the computer to the Line In port.
This will cause the audio to go out through the speaker port, then back in through the line where it will be recorded.Points from dubut knowedge base
Solution worked fine after visiting JB Hifi