Behind the scenes with Dermot O’Leary on BBC Radio 2

The broadcasters are clearly fond of each other, hugging hello, and O’Leary’s respect for Blackburn is palpable. The 74-year-old is something of a hero to O’Leary – who is 30 years his junior.

During their on-air handover, Tony tells his listeners that RT is in the studio today. O’Leary’s production team have been here for two hours already, with singer Plan B doing a sound check at 7am in preparation for his live performance later on in the show. O’Leary sits in the studio in front of his microphone reading over the running order. It may be early but the assistant producer DJ Shanazzle is heating up a homemade lamb curry for the team working the tech behind the glass, where I’m sitting. They’ve all been up since at least 5am so for them it’s nearer to lunchtime. O’Leary’s had a yoghurt for breakfast and he’ll snack on a banana at some point, he says, then he’ll tuck into that curry once he’s off air in two hours time.

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There’s a surprising sense of calm in the studio as the team gets ready to go live, particularly O’Leary, who is cheerful and composed.

“I’ve been doing this a long time, so over time the nerves and adrenaline have morphed into each other,” he says. “It used to be terrifying to switch on the mic and not know what I was going to say, but it’s been a long time and now I’m more confident.”

He says he loves live radio – “depending on emails we get from listeners, the conversations can go in interesting directions”. While he thinks about the show in advance and has to be focused, it must be liberating to walk into the BBC and get going, without the make-up and the colossal production team involved in The X Factor, which he’ll be presenting later today.

Every time a song starts playing, O’Leary waves me back over to his side of the glass to keep chatting. He had reservations about moving from his Saturday-afternoon show to the breakfast show last year, he says, because he thought he might not be allowed to choose the music. One of the provisos of him taking the new gig was that he’d pick music he liked and keep the bosses happy by playing two new songs from the charts every hour. Otherwise, if O’Leary wants Kate Bush, a 90s hip-hop track or an unsigned band he thinks are brilliant, he can have them.

“It’s different doing Saturday afternoons because you can play almost anything you like. But you have to be mindful of what the listeners might be doing on a Saturday morning and what the tone should be. It’s nice, though. Listeners might be taking their kids to football, or hanging around at home or cooking breakfast. I want to have a reasonably relaxed tone, but I’m given quite a bit of leeway.”

While O’Leary goes on air with his Pause for Thought guest, Reverend Matt Woodcock, RT heads off down the hall to meet Sally Boazman, or “Sally Traffic”, who has been delivering traffic updates at Radio 2 since 1998. On a screen in front of her there is a map of Britain covered in flashing lights, each one marking a traffic snarl-up. She gets calls from listeners with traffic updates and then cross-references them with the police, but there are a few listeners who have been updating her for so long that she knows their information will be accurate.

When Sally comes into O’Leary’s studio to do her report and sees the curry she says that in Terry Wogan’s day they had pizza for breakfast. Halfway through the show, listeners begin phoning in to play Mystery Voice, the competition where callers guess the identity of the person in a clip played on the show. The producer says they use their instinct when it comes to knowing whether a caller is OK to let loose on live radio, but they don’t get much trouble on Saturday mornings. It’s the evenings that you risk getting a sweary, drunk caller.

O’Leary doesn’t know who the mystery voice is – this one is American actor Roseanne Barr – so when a listener named Arthur rings up and gets it right, the producer does a thumbs up to O’Leary through the glass and cheers erupt from the team. “That one’s been going on for months!” the producer exclaims.

It’s still relaxed in the studio – nobody has snapped, lost their cool or used any expletives. It must happen sometimes, but the cameraderie is clear. Perhaps it’s something to do with everyone being thrown together on a Saturday morning while their partners and children are still asleep. The room fills up as Plan B gets ready to do his live set with his backing singers and sound equipment.

At 10am, it’s all over and the team is buzzing. “That was a good show!” beams Ben the producer. O’Leary tucks into some of the curry, puts his scooter helmet on and says he’s off home to Primrose Hill to have a coffee with his wife, TV producer Dee Koppang, before he races off again for The X Factor.

As we say goodbye, O’Leary reveals what gets him out of bed before 7am on a Saturday morning. “I love interviewing people,” he says. “People who come on as guests, but also the callers. It’s so good talking to them all, hearing their stories. It’s why I got into this and I say to younger broadcasters that unless they’re curious about humans, they shouldn’t do it.”

Dermot O’Leary is on Radio 2 on Saturday mornings from 8am