You dont need anything more than windows, stop making it complicated.
Open Volume Control>Options>Properties, select recording, tick "What U Hear", Ok
Tick "What U Hear"
Open Sound recorder > Press Record > Play Video > Press Stop.
Download any 1000's of wav > whatever sound file u want converters if wav isnt the desired out put.
This method is great for stealing songs off sites and turning them to MP3's. Saving streamed media... anything at all really.