OK. Ill explain as best as i can......
R2 : A Sphincter says what?
(Camera shot of Obi standing outside his ship)
Obi : What?
(Back to R2 in the ship)
R2 : A Sphincter says what?
(Again the same shot of Obi talking outside his ship)
Obi : What?
(Back to R2 in the ship again)
R2 : Exactly
Just like http://www.youtube.com/watch?v=vgJkLniLpfU&feature=player_detailpage#t=269s