Aniston 'unhappy with Mayer jokes'

Jennifer Aniston has apparently been angered by John Mayer joking about being unfaithful.

The singer told the audience during one of his recent live shows that he had been "dream cheating" and confessed to fantasising about "chicks" while sleeping.

Aniston was hurt by the singer's comments, say reports.

"One of the things that causes tensions between them at times is the jokes John makes when Jen isn't around," a source told Now.

"She wasn't happy when he told the audience at his show in California on July 26 that he had a dream he had 'made out' with someone other than her."