George Michael has been warned he will be sacked by his record label unless he curbs his wild behaviour.
Chiefs at Sony/BMG say he must control his cannabis abuse and stop drawing unwanted attention to his private life as well as seeking help for his apparent addiction to the drug.
Former Wham! singer Michael has just started a 50-date sell-out world tour - his first for 15 years - and will launch a new album commemorating 25 years in the music business next month.
The label and tour promoters have ploughed millions into the singer's relaunch.
However, sources at Sony/BMG described Michael's most recent arrest in the early hours of Sunday morning as "exasperating".
Michael, 43, was found slumped, passed out over the wheel of his car by police who arrested him on suspicion of being unfit to drive and for possession of what was believed to be cannabis.
It was the second such incident this year.
The openly gay star was also recently caught having a sexual encounter with a jobless 58-year-old van driver he met while prowling the woods of Hampstead Heath near his home in the early hours.
A well-placed source at his record label Sony/BMG said last night: "George seems to be getting more and more unpredictable.
"He is drawing attention to himself by his increasingly erratic behaviour.
"He is an adult and free to behave how he likes, but he must remember that the more indiscreet he is, the more he will be caught out.
"That is twice now he has been found slumped unconscious behind the wheel. He has also been photographed coming out of the woods with a grey-haired stranger in the middle of the night after some dodgy sexual encounter.
"None of this looks very good to his fans. He just doesn't appear to care what people think of him - it's exasperating.
"We're really banking on this comeback being a great success - and to be fair ticket sales have been phenomenal.
"But I'm not sure how much more of this fans can take. It is now at a point where we are going to have to warn him that he must start carrying on more responsibly or else we will have to seriously consider his future with us."
Defiant Michael spoke out last night to deny he had a drug problem.
He said: "That's the second time in a year I have been caught with one unused spliff (cannabis cigarette) in the car.
"I had no drink or drugs in my body. I haven't got a problem with drugs."
A friend added that his penchant for cannabis was linked to the fact that he was now a Buddhist convert and it helped his chanting - plus it makes him more creative.
"George has become a Buddhist convert and is praying every day. He continues to smoke weed because it helps him with the spiritual chanting apparently.
"He also says it helps make him more creative and is responsible for some of his best work in recent months," the friend said.
Michael's long-term partner, Kenny Goss, spent two months in rehab after checking himself in for alcohol abuse.
He is thought to be encouraging Michael to seek similar help for cannabis addiction.
At the weekend, Michael was found by officers after worried motorists dialled 999 to report his car was causing an obstruction at traffic lights in Cricklewood, north London.
Scotland Yard confirmed that police arrested the driver on suspicion of being unfit to drive and for possession of what was believed to be cannabis.
He was taken to hospital before being cautioned for the drug offence and released on police bail pending further inquiries on his fitness to drive.
Speaking of the incident last night, the friend added: "George had got back late from Toulon where he was performing. He was really knackered so I'm surprised he went out."
Michael was cautioned by police for possession of cannabis after being found in a similar state at Hyde Park Corner in February.
At the time he issued a statement claiming it was "my own stupid fault as usual", and later wrote a song inspired by the experience.
In April the singer was in the news again when he collided with three parked cars near his north London home.
Michael's spokesman said last night: "George is fine".