The 26-year-old's rendition of 'Sweet Dreams' by Eurythmics attracted criticism for the use of a "robot effect", with viewers accusing X Factor bosses of using Auto-Tuning to perfect her vocals.
In response, an X Factor spokesperson insisted: "If Kitty had hit a wrong note viewers would have heard it. This is nothing like Auto-Tuning and we do not use any effects which would materially change or mislead viewers."
Speaking to The Mirror, Brucknell expressed shock at the allegations that her performance had been anything other than natural.
"I can't believe people think I was Auto-Tuned. I have been performing on stage for nine years and never used it," she claimed.
"I didn't know they were going to add the effects to my voice. It wasn't my decision. They used a vocoder and afterwards when I watched it back I could hear it too. It was done so that it made me sound more like Marilyn Manson."
Brucknell stated that she has already warned the X Factor team that her performance next week should not be messed with.
"I trust the production team. They have made my performances look amazing on the live shows. But I'm going to insist they don't change my voice with any effects next week.
"I want people to keep voting for me and to vote for my voice. I have been working really hard and hope I have turned things around."
Brucknell added: "I wasn't in the bottom two this week thanks to my amazing fans. I will be gutted if this row ruins my chances."
> 'X Factor' Kitty Brucknell: 'Brits always go for safe and predictable'
Watch Kitty Brucknell's version of 'Sweet Dreams' on The X Factor below: