Perhaps you've heard the tapes of Elvis butchering the lyrics to "Are You Lonesome Tonight?" - well, here's the video. (If I've linked to the video correctly, you should jump write to the good part.)
There's always been speculation that Elvis is drunk (or high) here. Perhaps. I like to think he's just goofing around during the super-serious monologue part of the song. His pre-song banter would indicate that he's either extremely nervous or disoriented; so who knows?