I'm not watching it myself (sent the wife to her mothers to watch it there!) but it's likely the 'live' broadcast is actually on a short delay, with someone poised to switch the sound off every time the "celebrities" say anything defamatory or obscene (i.e. interesting).
Of course, it could always be because a kangeroo has eaten through a cable.
I think its a legal thing.
During Big Brother the same thing happens but they used to put a message on screen, cant remember what it said, but it was something about complying blah blah blah and broadcasting rules blah blah blah.
Not a lot of help but Im sure somebody else will elaborate. You could try phoning/e.mail the TV company they are sure to be able to help
It is indeed for legal reasons. Not just swearing and other such obscenities, but also if the celebs talk about other people not involved in the programme sometimes. Celebrity gossip we're not allowed to hear - v unfair.
but if you're a lipreader, you could clean up with scoops!
I better rephrase that ;-) you could earn money from journalists, with hot gossip. Or something.
It is also to do with copyrights and advertising rights and also for slanderous and personal protection reasons and of course the bad language issue. Nine times out of ten all of the interesting stuff is blocked out and all the rubbish boring stuff left if!!!!