I have no idea which episode it was, but the sample is from the German sounding doctor character that would sometimes get antagonized by the Wacko, Yakko, and Dot characters on the show. The vocal sample is of course the little blurb that comes on at the beginning of the track. I was stunned when the cartoon was playing the background to whatever I was doing and I recognized the sample. And I'm more than certain the track pre-dates when the Animaniacs show was re-released on DVD, which means that Domino or whoever in Hiero had to have recorded that on VHS to get the sample for the song.