In an interview with Medium.com, Spears’ manager Adam Leber confirms the lip sync accusations, explaining that the mother of two, 32, needs vocal help during her many dance-heavy numbers.
“To put on the show that she puts on, it’s virtually impossible to sing the entire time and do what she does,” Leber says. “She’s singing on every song, basically, when she has the ability to sing. There’s no way you can dance for 90 minutes straight and sing the entire time.”
The confession is a far cry from her rep’s original stance.
“Britney Spears will be singing live during her show (and) she will not be ‘lip-synching,” the publicist insisted before the Piece of Me show’s December 2013 premiere  at Planet Hollywood Resort and Casino.
Spears has been plagued by lip syncing complaints since her concert’s early days: In February, a video surfaced of the star experiencing a tech malfunction, yet suspiciously singing perfectly and just weeks later, Spears forgot to move her lips while what seemed to be a track played her new tune “Alien.”