American beauty Kristin Cavallari has denied reports claiming she has been romancing Nick Lachey.

The sexy 19-year-old - who shot to fame on US reality TV show 'Laguna Beach' which followed the lives of eight teenagers living in California's OrangeCounty for MTV - has been spotted in recent weeks canoodling with the hunky singer at a number of parties.

Rumor has it that Jessica Simpson and Maroon 5 singer Adam Levine first became romantically involved in 2004, according to eyewitnesses who have come forward with the news. Jessica and soon-to-be ex husband Nick Lachey constantly rebuffed rumors of infidelity during their marriage. However, according to witnesses photographer Andrew Sweeney and reporter Lisa Ladabouche, it wasn't Nick who was unfaithful, but "Dukes of Hazzard" star Jessica.

They claim Jessica and Adam hit it off a little too well after they both performed at a concert in Boston in May 2004. The witnesses stand by their story they saw the two musicians kissing in a VIP area backstage at the concert. Ladabouche says in reports, "I definitely saw them kissing. It was a shock, especially knowing her husband was away. And she's supposed to be this innocent figure."

Jessica Simpson and Maroon 5 star Adam Levine reportedly made so much noise in a Los Angeles hotel staff had to ask them to be quiet.

The stars - who have been at the center of romance rumors for months - are said to have been cavorting in a room at the swanky Chateau Marmont.

Rumor has it that simpleton singer and reality show star, Jessica Simpson is livid over reports that her soon-to-be ex-hubby, Nick Lachey and longtime best friend and personal assistant CaCee Cobb were getting their groove on with each other at a party thrown by "That 70's Show" star, Wilder Valderrama at the Los Angeles night spot, Level 3.

"The two were all over each other," reveals an eyewitness at the club, "Nick had his arms wrapped around her, and he was kissing her all over the side of her face and neck. Her arms were around him, too."

Former 98 Degrees pop star Nick Lachey is said to be completely over his simpleton soon-to-be ex Jessica Simpson. Rumor has it that he is now dating a former beauty queen, Elizabeth Ann Arnold, who was Miss Kentucky USA in 2002.

Elizabeth is now an actress that lives in California and appeared in the film, "Taking Charge," with Faye Dunaway. Nick's new girlfriend was born in California and moved to Kentucky when she was 11, then moved back to Cali to pursue acting. The two have been spotted all over together.