X Factor is using Autotune to enhance contestants’ voices, it has been revealed.

Angry X Factor fans have taken to the forums to vent their anger, claiming that Autotune is misleading audiences.

After the opening X Factor show, which pulled in 11.1 million viewers, fans picked up on the fact that some contestants’ voices had been digitally enhanced.

At the centre of the Autotune storm is 18-year-old Gamu Nhengu, who sang Katrina and the Waves’ hit Walking On Sunshine. Gamu is currently the bookies favourite to win the X Factor.

Judges unamimously voted Gamu through to the next round, with Simon Cowell calling her “really talented”. However, viewers picked up on the fact that her voice has clearly been altered.

MPs have also waded into the Autotune debate, with Labour MP Tom Watson telling the Daily Mirror: “It’s as bad as rigging the phone lines for voting.”

X Factor have defended the show, telling the BBC: “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.

 “When it gets to the live shows, it will be all live.”