Sam, 36, revealed before her audition that all her co-workers joke about her singing and "take the mickey", and laughed that she had made her pet dog deaf with all her warbling.
However, her cover of Beyoncé's 'Listen' was one of the highlights of the opening episode, blowing away all four judges.
"That's exactly how that song should be sung, you're singing for your life," Sam is told.
Referring to her job, Gary Barlow joked: "Cuff me now."
Watch the stars of The X Factor talk to Digital Spy below:
The X Factor continues on Sunday (September 1) at 8pm on ITV.
Photo gallery - The X Factor series 10, episode one: