Trouble in Pop/Rock Paradise?

They say money can't buy you love, but apparently it can sure cause trouble in a relationship when you're making more of it than your man. That's the good word from celebrity gossip hound Janet Charlton, who reports that all is not well between Hilary Duff and her BF, Good Charlotte singer, Joel Madden. Word is, this punk rock boy's ego has taken a major hit over the fact that Hil out earns him a million times over. "[Hilary] earns more in a week than Joel has in his entire career," says a source. To make matters worse, the two reportedly don't trust each other, and have taken to playing spy games (via cellie, e-mails, and even each other's bodyguards) when the other ain't around. "When Hilary is out with the girls and gets someone's phone number, she writes it on her hand -- so Joel can't find it in her phone." Wow, stars are just like us! (Minus the stalkerazzi drive-bys in limos, of course...)