They used his voice from an earlier scene. "Hang on, hang on, what's all this then" or words to that effect.
Edit: It might have been 'what am I supposed to do?'
Used to go in The Holgate, right at the back in the middle. My mate would always start off the BEEEEEE OOHHHH...
Then on some midweek games we used to jump the turnstiles in the North stand