Is Britney Spears Lip Syncing to Sia? 'Perfume' Scandal Hits Vegas

ETONLINE

Those backing vocals sound an awful lot like the "Chandelier" singer.

Britney Spears just can't catch a break.

Lip syncing controversy is nothing new for the pop star, but now singer Sia may be getting caught up in the drama. Here's the deal: Sia is credited as a co-writer on Britney's hit "Perfume," which Brit Brit performed recently at her "Piece of Me" Las Vegas residency. The problem is that the show's house vocals sounded a lot like Sia and not a lot like Britney, leading many to speculate whether the "Chandelier" singer's vocals were actually being used in the show. Take a listen for yourself in the video above.

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As Billboard notes: it wouldn't be unheard of for Britney to use Sia's vocals as an in-monitor guide while she performs, but that audio shouldn't be played out to the entire audience. However, sources tells ET that there is no truth to the Sia connection.

The news comes shortly after an alleged demo track -- read: no auto-tune -- of Spears' song "Alien" leaked online and caused a stir among fans. The vocals were notably raw and off-key, but producer William Orbit was quick to jump to Spears' defense.

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"I'd like to affirm that ANY singer when first at the mic at the start of a long session can make a multitude of vocalisations in order to get warmed up," he posted on Facebook. "Warming up is essential if you’re a pro, as it is with a runner doing stretches, and it takes a while to do properly. I've heard all manner of sounds emitted during warmups. The point is that it is not supposed to be shared with millions of listeners."

The audio has since been pulled from YouTube, but you can hear it in ET's video below.