I have a Win10 DeskTop System with an OnBoard Audio ChpSet.

I Right Click on My Speaker Icon on the Bottom Right Hand Side and Click on Open Volume Mixer.
All of My Sliders are Up and nothing is Muted.

Now I Right Click again on My Speaker Icon and Click Sound Setting.
Now Under InPut Device I Click Stereo Mix RealTek Audio.

And in Audacity I have MMe Selected as My Audio Driver.
And for Audio InPut Device I Selected WXGA TV because I have a TV as My Screen and I use the Speakers for My Systems OutPut.

Now I Open My Hulu App and Start Playing a Family Guy Episode.

I Try to Record a Sound to Play with and Edit it.

But I Pick up no Sound.

I always did this what am I Missing?

 

I always did this what am I Missing?

A possible software upgrade behind the scenes. More and more companies including Microsoft are helping protect copyrighted information and disabling features that facilitate copying copyrighted audio and video. Check all the vendors of the products you named. Likely states what was updated with each version number on their website somewhere.

 

I agree with MrSalts, the problem maybe in copyright information, but sometimes it could be hardware issues. I had the same issue as you, but it was with my synth recording (I tried to record some bass lines on my Korg Minilogue), but there was no sound at all. Maybe you should change your device? Microsoft's application are not good in field of sound... Or just try simple screen recording and then just change a format of file to audio.

 

Trying to record the output to the computer using software on the same computer is sometimes not possible without extra configuration. You might get some help from the Audacity manual.

Select WSAPI as the driver in the first box and you should see options to record your speaker output (loopback), that's what you want.