Simon Cowell must be really starting to wonder if the whopping £10million he paid out to get Britney Spears as a judge on the X Factor USA was worth it, as the short-fused-live-wire has gone AWOL from the auditions for a second time!

Not just this, but, according to the Sun newspaper, Cowell is receiving worrying daily updates from show producers, informing him of the singers behaviour as well as concerns that she may crack, whilst he is currently recovering from bronchitis.

This second disappearance came a fortnight ago when she left fans at the Kansas City arena shouting “Where’s Britney?” after  after an abusive contestant was mean to her.  Her constant need to run away is causing much concern amongst producers, who had to allow her fiancée on set with her at all times as he has the legal ownership of her mind after a judge granted him main executive of her estate following her famous hair-shaving meltdown (come on Simon, the clues were right there, you might as well have employed Susan Boyle for the job!)

According to the paper, Spears walked out over the contestants behaviour, leaving fellow judges L.A.Reid, Demi Lovato and Cowell’s stand in, our Louis Walsh, open-mouthed and wondering what to do with only three judges.

The contestant, who was quickly removed, became abusive to the panel having started singing facing away from them (he was obviously confused, he meant to audition for the voice obviously!), an audience member commented: “He had a very bad attitude.”

The three judges continued auditioning till the next break, with Britney returning for the next stage of filming.

A source said: “It’s embarrassing to have an empty seat on the panel in filming sessions as the footage is almost totally wasted. If a great singer appears and producers want to use the audition, you have to tell viewers why Britney wasn’t there. That’s not easy.

“Britney is getting £10million to appear and it could be the biggest gamble Simon has ever made.”

The first time Britney walked off was in Austin, Texas, on her very first day for similar reasons, with press instantly labelling her as g “unprofessional” for leaving her seat empty.

An insider said: “If she continues to behave like this it will get embarrassing.”

However, according to her manager, Larry Rudolph, this has all been blown out of proportion, with him commenting:“What is everyone’s problem? Every time Britney stands up or wants to go to the bathroom she gets accused of walking off. Everything is fine, Britney loves being on X Factor.”

Watch the judges arriving at the Austin, Texas auditions in the clip below: