Christina Aguilera has always had a high maintenance rep on 'The Voice,' but until now it was pretty much assumed to be tolerated since she's a fan and media favorite on the show.

Not so, reveals an insider source: The producers actually fine Aguilera for making tapings start late. What's more, rumor has it Adam Levine is even more disgusted with her diva behavior than the suits are, especially in regards to his runner up contestant Tony Lucca -- and their egos battled out before the final performance episode aired.

A source told Radar Online that Xtina is "consistently two hours late," which isn't really something you can blame on traffic or anyone else -- that's plain inconsiderate. The source revealed that the show is actually charging Aguilera undisclosed amounts for her tardiness since it holds up production and inconveniences everyone who acts professional and actually gets to work on time. Problem is, the fines are small enough that they haven't deterred her, in part because, well, Aguilera's pretty loaded.

That's about to change, though. “For Season 3 this has got to stop," the source said. “Whatever her fine is now doesn’t bother her. She has so much money she probably doesn’t notice. Higher-ups on the show want to raise it to a number that does bother her so she actually arrives on time.”

Fellow coaches Levine, Cee Lo Green and Blake Shelton aren't too pleased with Aguilera's scheduling issues, either. “They can’t stand how late she is," the source said. "They know she’s a girl and she takes longer to get ready, but this is ridiculous. And when she gets to set she still has to go through hair and makeup.” And we all know that can take a while.

Levine and Aguilera, who once harbored a brother-sister like relationship on the show, are now said to be at one another's throats. Aguilera, who picked on Levine's contestant Lucca all season, reportedly was offended by Levine and Lucca's '99 Problems' song choice for the finale, believing the Jay-Z classic to have been directed at her. The source said that Aguilera may well have been on to something there.

“Christina found out that Adam planned to have his finalist, Tony Lucca, sing 99 Problems by Jay-Z, in which he'll sing 'I've got 99 problems but a b---- ain't one'," the source dished. “Adam and Tony wanted to call Christina out as a b---- but make it clear she's not a problem for Tony. It was completely aimed at her. It was Adam’s idea, but Tony absolutely loved it.”

Tensions rose when NBC told Levine to change the "b----" in the lyrics to "chick," which really set him off, since he believed changing the words would completely ruin the song. As a result, Levine went off on Aguilera during coaches' rehearsals of 'Free Your Mind.'

“Adam went right up to Christina and said ‘you’re the biggest f---ing c---,'” the source told Radar. “Obviously Christina was appalled and hissed that Adam should be fired. She’s sick of being treated this way. Christina is so sick of Adam being looked at as the golden boy of the show," the source added. "If America knew how disgusting he was, they would be appalled, she always says.” The source said that Levine was so P.O.ed that he locked himself in his trailer and it was unclear if he'd even participate in the performance. Yikes!

While we agree that the name calling was completely out of line, but since Aguilera hasn't exactly been an angel herself, we don't think she has any right to say who should and shouldn't be fired from the series. Considering how much money both of them make, we think they can afford to get a therapist on set to mediate the issues they're dealing with -- and if Aguilera can afford a guy to rub her feet on set, she should be able to spring for an alarm clock without a problem.

Watch Tony Lucca Perform '99 Problems' on 'The Voice'