if you right click on the little speaker icon in the task bar and then go to Voluem controle.
Once there, go to Options then Properties.
Once there you should see two or three radio buttons taht say Playback, Rcord and one MIGHT say Other. Click on Record and in the little menu under it, Check Stereo Mix and hit ok.
You'll then get a bunch of volume sliders for audio inputs to your computer. Click the check mark box under the one that says Stereo Mix and then everytime you go to record something, it'll record from your computer instead of your microphone.
WARNING: Make sure you don't have your volume up too loud or everything will sound VERY distorted.
NOTE: if you can't click the Record radio button, then go to the little dropdown menu a bit above that and pick the one that says Audio Input. It'll say your sound card name then Audio Input
EXAMPLE: RealTek HD Audio Input.
I hope that helps you out.
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