A sound expert has told the Who Wants To Be A Millionaire? trial that 36 coughs were made by one person during an episode allegedly won by cheats using coded signals.
Tecwen Whittock says he had an allergy
Dr John French said the noises could be traced to the show's 'Fastest Finger First' row of contestants, which included defendant Tecwen Whittock, a college lecturer.
Dr French said a total of 192 coughs had been recorded during the filming of the contested episode - but he said most of them had come from elsewhere in the audience.
Mr Whittock, who is accused of using coughs to help Major Charles Ingram con his way to the top prize, has admitted that at least some of 19 of those heard may have been his.
But he denies conspiracy to "dishonestly procure the execution of a valuable security" - namely the quiz show's £1m jackpot - as does Mr Ingram and his wife, Diana.
A studio sound supervisor told the jury that the "worst coughs" he had ever
heard on the show came from Mr Whittock.
Kevin Duff said he was operating the mixing desk during Mr Ingram's run to the grand prize, when he noticed Mr Whittock's "persistent"
But Mr Duff said he was not able to discern any pattern to the coughs at the time because he was so busy.
"There is normally coughing in the show... but this was more specifically a persistent cough."
The human brain can actually determine things the microphone can't
Dr John French
Later that evening he was asked to watch a recording of the major's
Prosecution lawyer Nicholas Hilliard asked: "During the viewing of the tapes you were able to identify specific coughs that could be heard immediately after Mr Ingram had read aloud what ultimately proved to be the correct answer?"
Mr Duff replied: "Yes, yes I could."
The court had heard that Mr Whittock told police that Mr Ingram would have been "very brave" to try to distinguish between different coughs made behind him during the show.
But while Dr French admitted that analysis of coughing was still in its infancy, he said that what Mr Ingram heard through the microphone would have "approximated" the real sound in the studio at the time.
And he said the "human brain can actually determine things the microphone can't".
Dr French said: "We have two ears which help us to determine directionality so a
person receiving sound... would have a very sharp indication where that sound
"He would also be able to determine distance."
Mr Whittock, a father of four from Whitchurch, Cardiff, told police when interviewed that any link between his coughing and the officer's right answers had just been "coincidence".
The prosecution claims that Mr Whittock used "particular" coughs to guide Mr Ingram, from Easterton, Wiltshire, to most of the correct answers.