Kate proved she could rock the house better than William when the couple tried their hand at scratching vinyl records during a visit to a youth project in Adelaide.
The royal couple were welcomed to the suburb of Elizabeth by 15,000 cheering fans who had turned out to greet them in the sunshine.
At first neither seemed keen to have a go on the turntables, each insisting it was a job for the other.
William, 31, told his wife "It's all yours", gesturing for her to come forward, but Kate, laughing, demurred and said: "William's got lots more experience than I have."
The 32-year-old Duchess, who wore a pale pink outfit by Alexander McQueen, took up the challenge first and, coached by DJ Shane Peterer, 28, started off hesitantly but soon got the hang of it.
As her confidence grew, she laughed and gave a thumbs-up as her audience cheered and applauded her new-found skills.
William then stepped up to try scratching, moving the record backwards and forwards so the deck's needle made a noise in the groove.
But his efforts were not as good as his wife's, prompting Mr Peterer to suggest he should not give up the day job just yet.
The DJ said: "She was fantastic but he can fly a helicopter. So, horses for courses."
The royal couple went to the DJ-ing lesson at a community music centre called Northern Sound System, and were on a mission to see a different side of Australian life in Adelaide.
They went to the garden suburb of Elizabeth, built in an era of optimism in the 1950s and named after the Queen, to meet young people and promote efforts to regenerate the area.
Elizabeth is one of a number of once-thriving blue-collar suburbs which have seen the industrial jobs that attracted their original settlers disappear, leaving high youth unemployment and a reputation for crime and violence.
Many of the original settlers were "Ten Pound Poms" who came to Adelaide from Britain at the invitation of the South Australian state government on assisted passage on ships with the promise of "sunshine and oranges".
But the jobs they came for, and now taken on by their descendants, are disappearing, with many employers closing their operations or planning to shut factories.
During their visit, William and Kate unveiled a plaque for a planned new office development named Prince George Plaza after their baby son.
It will be the focal point of a blueprint to make Elizabeth the second biggest business centre in the state.
The royal couple arrived in the city after spending the night camping under the stars in a boutique resort at Uluru.
Outside the music centre, they watched a skateboarding display in a nearby skate park and were presented with a customised board for George.
The gift had the baby's name painted on it and, as a reminder of where it had come from, it was also adorned with the image of two kangaroos and two Australian flags.
Some of the crowd called out to the Duke to "have a go on it" but he politely declined and handed the skateboard to someone in his entourage.
William showed his creative side when he used a spray paint can to make street art, holding a mask over his nose and mouth as he added to a design.
He first watched a team of painters from the Aerosol Angels group, which encourages young people to express themselves by creating graffiti art at the centre in a controlled way rather than by defacing public buildings.
When it was his turn, he added to a mural design that was part of a panel making up the name Playford, the area the royal couple were visiting.
Artist Casey Zechef, 16, said: "I asked him if he would like to have a paint. He said yes, so I got him to paint a bit of blue. He loved it. He didn't want to stop. He said it was fantastic - it was so easy.
"He was a natural at it. I was very surprised at how good he did. When you use a spray can for the first time some people don't use it so well. You have to get used to it. But he was a natural."
The 16-year-old painted baby George's skateboard and she said: "They loved it. They loved the kangaroos on each side. They thought it was amazing."
With the spray painting over, the royal couple watched a BMX riding display and followed their host 15-year-old Luke Haldenby up the steps to a viewing platform.
He said proudly: "I think I was chosen to do it because I know my stuff. I've got my brother to thank for that because he got me into riding - and that's what I told the Duchess."