Mariah Carey‘s acting success is more than a sore spot with hubby Nick Cannon.

Competition between Mariah Carey and hubby Nick Cannon looks like it is causing more friction in their marriage.

When the couple wed in April 2008, Nick "wasn’t prepared for her to lord over him the way she does," a friend told The ENQUIRER.

Nick, 29, believed they could make their two-career marriage work – he’d be the actor in the family, while Mariah, 40, stuck to singing.

But Mariah’s recent success on the big screen has gone to her head, says the friend, who also claims that Nick lashed out at her after she rubbed it in his face.

"I think it bothers him that Mariah is a hotter film property than he is right now," maintained another source.

Mariah followed her well-received role as a waitress in 2008’s Tennessee with an eye-popping performance as a social worker in the Oscar contender Precious.

"Mariah reads every review she gets and loves to show them to Nick," the friend said.

"Nick told Mariah early on how fickle Hollywood is and she shouldn’t get her hopes up to be a movie star. Turns out she’s eclipsed Nick’s acting career by leaps and bounds," added the source.

Wonder if Nick pulls out her battered copy of Mariah’s big screen bomb Glitter to remind just how fleeting it all is?