Joss Stone: 'England doesn't like me any more'

7 was not Joss Stone's year. The 20-year-old from Devon made a fool of herself at the Brit Awards, released her least successful album to date, sacked her managers and told her parents to leave her alone. So, Craig McLean asks her, how does it feel to be a proper soul diva?

Joss Stone doesn't know what all the fuss was about. She walked on to the stage in front of the TV cameras at last year's Brit Awards, unveiling a new look – all multicoloured mini- dress, purple hair and high heels that accentuated her 5ft 11in frame – then spoke a bit, sang a bit, came out in support of Amy Winehouse, cracked an unfunny joke about host Russell Brand, and sent "big, big love" to Robbie Williams, who'd just gone into rehab.

"I don't get it," she sighs. "Still, I suppose if you wanna change your hair colour and do different things with your life, people get upset."

No kidding. The day after the ceremony, Stone – who was still a teenager at the time – was pilloried mercilessly in the newspapers and in postings alongside YouTube clips of the show. I suggest to her that people were annoyed by the fact that the soul singer from Devon, born Joscelyn Eve Stoker, had boomed into the microphone in a diva-esque American accent.

"At the end of the day, I don't give a fuck if people have a problem with my accent," she says mildly but defiantly. "That's all I can say about it. The words I say do not change. If the way that it sounds is skewwhiff and you don't like it, don't listen. I'm not being a cruel person by sounding a different way. And I can't help it. I've been [in America working] since I was, like, 14. All I'm doing is working. I do my job, and I go home."

Stone first came to (fleeting) public attention in the UK in 2001, when she won the pre-X Factor TV talent show Search for a Star. But the barely adolescent girl with the staggeringly accomplished soul holler was subsequently signed and mentored by a US-based producer. Stone recorded her first album, 2003's The Soul Sessions, a collection of cover versions, in Miami, and spent most of the following years touring America. Among myriad accomplishments, she's duetted with Stevie Wonder and Gladys Knight, sung for George W Bush (twice), and performed at the Superbowl. Oh, and she's been round to Tom Cruise's house for takeaway Chinese food. So maybe it's not so odd that, when I previously interviewed her, in New York in December 2006, a couple of months before that Brits appearance, her conversation was full of American-isms: she'd just finished making her new, third "rekkid" – despite her dyslexia, don't go thinking she's "stoopid".

Her raunchy new image – a far cry from the floaty hippie vibes that accompanied her seven-million-selling first two albums, a barefoot look that had seen her nicknamed Joss Stick at school – was the product of her wanting to wear "whaddevva the fuck ah feel!" Now, talking in London almost a year on from the Brits debacle, Stone, who turned 20 last April, sounds like the middle-class white English girl she obviously is.

"Well, it [my accent] changes," she shrugs. "I made my album with a bunch of Americans. When people go to Australia for two weeks they come back sounding Australian – but the whole world doesn't turn round and say, 'Well, fuck you.' Which is basically what England had done [after the Brits]. Obviously not everybody in England. But the big press people. They were just like, 'You know what? We've decided we don't like you anymore.'"

Russell Brand had a go from the stage, didn't he? (Something along the lines of, "Joss Stone's still ranting backstage... I think we'll have to bundle her into a van soon... I'm a bit worried about [her], poor cow...")

"Russell Brand was a right bastard, that one. Especially since he was an alcoholic."

That's "ex-alcoholic", it should be noted, and ex-drug addict, and ex-sex addict...

"Bollocks! It's all bollocks. It doesn't matter what he is, the fact of the matter is he shouldn't really..." In much the same way as the UK media's enthusiasm for her did post-Brits, Stone tails off.

That chilly February night – and the tabloid-frenzied morning after – was but the beginning of 2007's annus horribilis for Stone. She attempted to explain her Brits "performance" on Chris Moyles' Radio 1 breakfast show but only sounded like she was moaning about being rich and famous. Three weeks after the ceremony she blew the live unveiling of her new album, Introducing Joss Stone, by arriving on stage at London's Koko club an hour late. Backstage at the gig, her dad and little brother had a fight.

"Yeah, that was interesting!" she laughs. "Real lovely, that one. My family are like that, though. It just tends to be the way, they fight a lot."

What was it about?

"I don't know. I still don't know. Harry was drunk, Dad was drunk, they had a bit of a scuffle. My brother's 18 now. He is a baby. But boys fight. Isn't that normal? It's normal in my family!"

Then it was alleged that she was smoking too much dope, that she was lonely and bereft after breaking up with Beau Dozier, son of Motown songwriting legend Lamont.

She is, she says, currently single. "I've had kinda bad luck with the blokes, so I'm probably just gonna let it be for a minute. I'm not in the right space to do that – they just don't tend to be too kind." To illustrate her point, she gives me a quick, room-filling belt of a new song she's just written – "Mr Wanker Man! Wanker!" she sings, but she insists it's not just about her ex. It sounds like a good follow-up to a song she wrote for, but ultimately didn't include on, Introducing... It was called "Not Real Love (I Wish I'd Never Met You)". Stone doesn't do mealy-mouthed politesse.

Most unappetising of all, shortly after "Koko-gate", Dallas Austin, a famed American R&B producer, appeared on a video posted on YouTube, making unsavoury – and completely unproven – allegations about female soul singers, Stone among them. He claimed they swapped sexual favours for production work on songs. "All these bitches be fuckin' for tracks," was his charming claim. Unsurprisingly, and no doubt after some swift legal advice, the video quickly disappeared from the file-sharing site and Austin issued a statement: "Every action generates an equal and opposite reaction. My statement about Christina Aguilera and Joss Stone was a reaction to an incident I care not to discuss in any forum, and while I may have felt justified, I do owe an apology to Christina, Joss and their families." Perhaps unsurprisingly, Stone prefers not to talk about this incident.

But it wasn't all doom and gloom: Introducing Joss Stone entered the US Billboard chart at number two, the highest ever first-week placing for a British female artist. The album featured contributions from stellar talents such as reclusive icon Lauryn Hill and highly regarded rapper Common. It also featured (on a spoken word intro) Vinnie Jones, but never mind. She duetted with Natalie Cole on a version of Nat King Cole's "L-O-V-E", and sang the song on a Chanel advert featuring Keira Knightley. Then, in a three-week period last summer, Stone appeared at Glastonbury, at the Wembley Concert for Diana (with Tom Jones), and at the South African leg of the Live Earth extravaganza.

Does she think that the planet-wide climate-change mega-concerts worked? "Probably not. But it's no reason to stop trying is it? [Oprah Winfrey's] O magazine asked me to write a little paragraph the other day for [an article called] "A Million Ways to Save The World". And the only way to save the world that I could come up with is if we pack our shit and leave. Cos we are the death of this world, man. We know we're the ones that are ruining it, yet we still carry on with our lifestyles. And I do too. I try to think about recycling and turning off the tap and turning off the lights. But then again I still have to travel, I still have to live my life... People think the world's gonna blow up. That's not the case. We are probably going to blow up, we're going to disappear... So I just think if they really, really wanna save the world, we should just go to a different planet." And no, Joss Stone isn't on a different planet already.

Nonetheless, for all this high-profile activity and trans-atlantic success (Stone toured the US twice last year), her third album didn't overly bother the British charts. The teenage soul sensation had heralded Introducing... as her ' most personal record. She had (co-)authored some 60 tracks for it, and wrested control of her career from her music biz mentors, sending an email to "everyone I knew", including her parents, telling them to leave her alone while she made the album. "It was really important that it was from me," she had told me in New York. "So if it goes wrong, I can blame it on myself. I won't blame it on anyone else."

'Basically, the record company didn't promote it," Stone says now when I ask her why she thinks her third album didn't sell very well. "That week all the [Brits] shit happened, they said, 'We're just gonna cancel your promo [promotional appearances] – we're gonna cancel everything that you have organised.' And it's not like one country wants me to do promo – I have to do promo literally around the world."

So they cancelled the whole lot? Why?

"Yeah – they said, 'It's best for you to just chill for a minute, then come back later and do it.' So now they want to release [new single] 'Baby Baby Baby', I have promo again. And I'm like, 'Well, I've just been working for a year and I'm going to sleep!'" But she can't drop out and crash out just yet.

Although she bought a house in Devon a couple of years ago, Stone more or less lives out of a suitcase, and true to form, she has flown to the UK today from Australia, via a "layover" in Los Angeles. She has been largely absent from the UK music and media landscape since last summer but she's come back home to film a commercial for Cadbury, in her guise as the new "Flake girl".

Two years ago she made her advertising debut as a face of Gap, but Stone says it's funny that she's been asked to front the Flake campaign, since she had a dream about Cadbury early last year, and tried to contact them to discuss making her own chocolate bar.

"I've noticed that many women in the public eye want to [promote] things like slim pills and how to look beautiful and how to be thinner and how to have bigger breasts and all these perfumes and whatever the hell it is," she says in the breathless, tumbling, girly way I remember her speaking in when I first met her four years ago. "Which has its place. But I thought, maybe I could just do something to promote chocolate, cos it tastes good! And that's what women need in our lives. Whenever you're feeling low, have a little bit of chocolate. I think people need to stop worrying about being skinny and things like that. Obviously don't be a fat bastard, cos then you'll be more depressed. But you have to enjoy the little things in life like that."

When the Cadbury people approached her, she says, the coincidence was too uncanny to turn them down. "I had a dream about it! I can't say no after all that. It sounds like a made-up story but it's true."

In its advertising history Flake has traded on what might be called phallic imagery. Is the new advert anything to do with a gypsy girl in a poppy field suggestively eating a chocolate bar? "The whole blowjob thing, yeah," she giggles. "My mum said that. She came down with me to the pub to meet the guys at Cadbury. She was like, 'It's not going to be like, you know, the BJ thing that they do,'" Stone recounts. "I was like, 'Mum, oh my God, sharrup!' They said no, it's a whole new take on it. It's just normal and chill. That's why they have me [in the advert] wearing normal clothes, writing a song, doing my work. Just doing what I normally do." Nonetheless, an artist manager might have counselled against Stone taking on this commercial. After the year she's had, and given her speaking style – which manages, rather brilliantly, to be both blunt and spacey – the campaign is a gift for the snarky: insert your "crumbliest, flakiest..." joke here.

But Joss Stone doesn't have a manager. Having taken control of her not-inconsiderable fortune from her parents a couple of years ago, she's also been managing herself for the past 12 months or so. She claims she was badly betrayed by her last managers, people she counted as close personal friends – they "literally", she says, "disappeared" from her life at the end of 2006. Previous managers have laid into her in newspaper interviews.

"I think I realised I needed to do it myself when I was at this party after the Grammies two years ago, and a guy came up to me and he was like, 'You know, Joss, we spoke to your manager about you singing a duet with Sting. He really wants you to cut it. And they told us you didn't want to do it and you just passed.' I was like, 'That's not true!' I would never ever, ever do that. Firstly, it's Sting, so oh my God! And secondly, it doesn't matter who it is, I still wanna have the choice, I still wanna be told... And this year there's been lots of things that have got done that I probably wouldn't have even been told about before."

But equally, some might say that if you had management, some of the mistakes that have been made in the past year...

"There's lots of mistakes," she interjects.

...wouldn't have been made, such as coming on late at Koko.

"That was not me. That was not a management decision. That was the promoter. It was promoted at the wrong time. I was there, on time. The funny thing is, my booking agent came to me a week later and was like, 'I'm sorry, that was completely my fault.' I was like, 'Well that's really nice and everything. But nobody is saying that it's your fault – the fact of the matter is that my name's the one on the top of the stories."'

Given the grief and abuse Stone has had from the press this year, does she feel sympathy for Amy Winehouse?

"Yeah, I hate what they're doing to her. They love it when it goes wrong. When there's issues, when there's a story."

Arguably, she's brought it on herself, more than you have... "Yeah, well, that's true. But the thing is, it's not her. She's not managing herself. It's not her that's booking the gigs. Her manager is doing that, and her record company is doing that, and her booking agent is doing that. And they shouldn't be allowed to do that to her. And they're taking the money from her, they're taking the percentages. They're pimping her out, and they're raking in the pounds while she's getting worse and worse."

Despite a troublesome year, despite weathering a storm of negative press, downright nastiness and betrayal, Stone is far from getting worse and worse. No Britney-esque, Winehouse-shaped rehab-headed spirals here. For a woman barely out of her teens, who's lived almost a third of her young life in the public eye, she seems remarkably sorted. No, 2007 was not a good year. And Introducing Joss Stone was not a good record. But it's early days. She'll be back.

Before I leave her to eat her way – non-suggestively – through an afternoon's worth of chocolate bars, I ask Stone what she has learnt from last year.

"I've learnt that some people are arseholes, generally," she replies with a not-bothered smile. "And that you can trust no one but yourself."

See. She's got her accent sorted out already: she didn't say "assholes".

'Baby Baby Baby' is out now on Relentless. Joss Stone's Flake adverts will be on TV this spring, www.cadburyflake.com