An award-winning record producer has defended the X Factor over claims that the TV talent show used technology to make some contestants' voices sound better.
Most of the allegations surrounded teenage contestant Gamu Nhengu, who sang a version of the Katrina and the Waves' hit Walking On Sunshine.
After hearing her effort, judge Simon Cowell told the 18-year-old from Clackmannanshire, Scotland, she was "really talented" before she was unanimously voted through to the next round.
But some viewers went online to accuse the producers of using autotune - used in studios to improve performances by correcting pitch and disguising off-key mistakes.
On the show's website, robhayes wrote: "Absolutely disgusting use of..autotune...does X-Factor really think we are idiots ? I see the idea of making the show more entertaining , but this is taking the mick .. really .."
Smstrat91 added: "Cannot believe they autotuned her, listen to the words 'door' and 'telephone' and its very clear. Shes so good aswell, but obviously the producers of xfactor didnt think she was good enough."
Similar accusations were made about another contestant, G and S singer Caroline, who also made it through to round two.
But Donal Hodgson, who won a Grammy for his work with Sting, said using it was perfectly acceptable as long as it was not a total "fabrication".
He said: "The issue would be if The X Factor was using it on people that really couldn't sing and making something that was a fabrication.
"I didn't see the show but I imagine if you have a lot of young people who have never sung live on stage before then they will sing out of tune.
"They won't be used to monitors and hearing their own voices coming back to them so they would be more likely to sing out of tune."
He added: "Of course, if The X Factor fabricated the whole thing it would be self-defeating and they would end up with someone who couldn't sing."
'Entertaining experience'
A spokesman for The X Factor said post-production work was necessary due to the number of microphones used during filming.
"The judges make their decisions at the auditions stage based on what they hear on the day, live in the arena.
"The footage and sound is then edited and dubbed into a finished programme, to deliver the most entertaining experience possible for viewers."
With judge Dannii Minogue on maternity leave, Simon Cowell, Louis Walsh and Cheryl Cole were joined by Spice Girl Geri Halliwell to give their verdicts on the best (and worst!) of the wannabes.
More than half a million people in Northern Ireland tuned in to UTV on Saturday night for the opening night of the show's seventh series.
"What an incredible return for X Factor on UTV," said Michael Wilson, Managing Director, UTV Television.
"These viewer ratings show that X Factor is still a firm favourite for the audience here and this series is more popular than ever with our audience."
With an average 60% share of viewers, UTV had the highest audience ratings in the ITV Network - well ahead of the network average of 46%.
Missed The X Factor? Catch up with the UTV Player.
© Press Association