"Julio Bungholio! He will be an albino! And a gringo..." Classic.
And Beavis' voice seems to be most noticeably different when he's screaming. Talking is only mildly different. But seeing as his under his breath, "How's it goin'" sounds the same, it's not bothering me too much. I mean, speaking of South Park, Cartman's voice has changed radically since the start, to the point where now if you go back and watch old episodes, he sounds weird and off-putting.