When a radio station makes more than 40 changes to a record so they can play it, the DJ must be pretty keen to get that record on air.
If that record were the shocking new hit from Eminem or Madonna, this enthusiasm would be impressive, but not unheard of. When that record is actually the debut single from an unsigned artist, there's only one likely conclusion: the DJ thinks he's stumbled upon something special.
Azealia Banks, a little-known rapper from New York, gave away a track called 212 as a free download from her website last September. Following 40-plus changes to its lyrics, BBC Radio 1's Nick Grimshaw made it his Record of the Week. He wasn't the only music industry tastemaker who became instantly smitten. In November, Banks topped the annual "Cool List" compiled by UK music weekly NME. it was then included on numerous "best songs of 2011" lists assembled by newspapers, websites and music magazines.
Gwyneth Paltrow and Kanye West also declared themselves fans of the rapper. The Scissor Sisters were so impressed that they invited Banks to appear on Shady Love, a single they released at the start of the year.
What is it about 212 - named after the telephone area code for Manhattan - that made Banks such hot property? The rapper's use of language, too rude for radio 40 times over, certainly grabs the attention. But swear words are hardly anything new in the rap arena. What's really impressive about 212 is Banks's attitude, her knack for a hook and her versatility. She slips in and out of different characters like an actress.
That's an apt comparison given her background. Azealia Amanda Banks was raised by her sales assistant mother in Harlem, New York, after her father died of pancreatic cancer when she was two years old. The youngest of three sisters, Banks showed an interest in the theatre from an early age. When she was 10 she began appearing in off-Broadway musicals and later attended LaGuardia High School of Performing Arts - well-known as the school that inspired Fame.
After dropping out of LaGuardia to focus on music, Banks worked as a barista at Starbucks to fund her first recording sessions. Her efforts soon bore fruit. Using the alias "Miss Bank$", she began posting her songs online and attracted the attention of XL Recordings, a prestigious British independent record label which is also home to Adele, Radiohead and MIA.
On paper, it seemed like a dream combination: Banks was gifted and ambitious, while XL had a proven ability to nurture new talent. In practice, Banks claims she and Richard Russell, the label's owner, experienced creative differences right from the start. He responded, Banks alleges, by having his team ignore her.
"It was almost the day that I signed to XL that they started checking out," she told the BBC last year. "There were a good seven to eight months where I was just sending them texts and no one would say anything or pick up the phone or respond to my emails."
Banks became so disheartened that she cut all ties with XL and retired her cumbersome alias. She ran away to Montreal, regrouped and began recording under her proper name. Then she got her revenge with the success of 212. Following its popularity on the blogs, the single became a mainstream hit, peaking at number 12 on the UK charts in January. The same month, Banks completed a remarkable comeback by signing to Universal Records.
This is where the hard work really begins for Azealia Banks. She now faces the challenge of matching 212's intensity across an entire album. The early signs are encouraging: several impressive teaser tracks have appeared online since her surprise breakthrough. However, she's hit some bumps in the road too.
In April, she signed a potentially lucrative management contract with Troy Carter, the man who handles Lady Gaga's business affairs. Understandably, Banks was excited, telling Twitter that she had "a whole new set of resources to take advantage of". But on June 7, Carter announced that he "ended the business relationship with Azalea last month on very amicable terms". Banks is now reported to be working with David Holmes, an experienced rap manager who, according to music industry rumours, is also her boyfriend.
Before this upheaval, Banks had hit a more obvious glitch. In April, she was forced to cancel almost all of her summer festival appearances in order to focus on recording. One thing Banks lacks is time: her debut album, tentatively titled Broke with Expensive Taste, is scheduled for release in September. In the meantime, Banks has just put out her debut EP. Named 1991 after the year of her birth, it's an obvious stopgap, but one that bristles with promise. The song 212 still sounds fantastic, but the EP's three other songs don't feel like poor relations.
A track called Liquorice, which first appeared online at the end of last year, is Banks's distinctive take on interracial dating. It's predictably filthy, but also clever and verbally dexterous.
The EP is completed by a pair of brand new recordings. On Van Vogue, Banks squares up to female rap rivals like fellow New Yorker Nicki Minaj. "Where's my crown?" Banks asks presumptuously, before making a prediction: "They all forget you when I spin this sh*t."
The EP's title track is just as sassy. Banks brags about a trip to Paris, her rapid progress in the music industry, and her ability to pick which beats she raps over. She also offers a succinct summary of her origins and destiny: "NY rose me, most high chose me."
However, Banks has released an even more promising song separately from the EP. Last month she gave away Jumanji, a calypso-tinged track that sounds like the missing link between MIA and Nicki Minaj. It could be her biggest crowd-pleaser yet, something Banks acknowledges when she raps that "ya aunties, nanas and grandmas" can "jam" to it.
Before she completes her debut album, Banks will have to reconcile her hipster credibility and street appeal with her obvious commercial potential. With characteristic savvy, she's already given the issue some thought. Back in January, she told the British broadsheet The Guardian: "As much as I want to remain artistic, let's not get twisted. In five years time, I'm going to be 25. I need to make money. That's why I'm not afraid to be popular. That doesn't mean I'm prepared to do anything to get attention - wear a wig this high or get plastic surgery."
As her career progresses, it's going to be fascinating to see where Azealia Banks draws this line. But she already knows that when she's on top form, radio stations will bend over backwards to play her, so she's unlikely to worry too much about minding her language.
Nick Levine is a freelance music journalist based in London.