Well, for one, I'm not AoO, even if we have the same musical taste
I honestly don't ever remember that... I've been using that line myself for a couple years whenever I want to mock Seinfeld's "Whyyyy..." style
They were watching the video for "Funk Dat" (by Sagat?), and Beavis did a couple himself (the "taking/leaving a dump", as well as "why is it, after I pick my nose, it;s full again in a few minutes? Funk dat.")
And I'll 3rd Newsradio. Season 5 is pretty hit or miss, but I love everything before that.