Fru Hazlitt isn't feeling too hot. It is the first week back after the Christmas break and her three young daughters have been ill over the holidays, leaving her feeling more exhausted than during a normal working period.
But after a few minutes of conversation it is hard to tell Hazlitt is anything other than 100 per cent. Famed for her forceful personality and talent as a public speaker, she is a garrulous interviewee.
She arrived in her corner office at Virgin Radio's Golden Square headquarters four months ago and is about to oversee the most important change at the station in years - the launch of Christian O'Connell's breakfast show on 23 January.
Previously the UK managing director of Yahoo!, Hazlitt also likes a challenge.
She joined Yahoo! almost six years ago from Capital Radio at the time of the dotcom crash, then decided to leave once it became successful, to join Virgin Radio at a time when commercial radio is generally in the doldrums.
She says: "Virgin is a station whose fame is disproportionate to its performance now. There were two important things for me. One is the brand, which is something that matters to people; two is working for people that I respect."
Hazlitt,42, says that she hit it off with Andrew Flanagan, the chief executive of Scottish Media Group, Virgin's owner, who has promised to give her plenty of room to operate in her role as the chief executive of Scottish Media Group Radio.
She was also keen to return to radio, having worked for Capital Radio in the 90s, latterly as its sales director. Until four months ago, she was last in Virgin Radio's Golden Square building in 1997, when Capital came within a hair's breadth of acquiring Virgin Radio only to be scuppered by Chris Evans' rival bid.
So how has she found Virgin? "It staggered me that things here were exactly the same (as nine years before). It's amazing that it still has the soul which reminds me of walking into Capital 13 years ago. It's a 'love' culture here and I couldn't believe that it would manage to keep it, given that Virgin Radio has such a bruised history."
Hazlitt says she is sorry that, in her opinion, the owners of Capital have not pulled off the same trick. "I feel absolutely gutted about what has happened at Capital, because I was one of those people who thought that going into the Capital foyer was the most exciting thing. What has happened to Capital is bad for radio. There are mixed feelings - of course, it is an opportunity but Capital is a mighty player, so its woes affect the industry."
Supporters of Hazlitt say she is the right choice for Virgin. Nick Manning, the chief executive of OMD, worked with her through his agency's relationship with Yahoo!. He says: "She is one of life's great enthusiasts. What she is good at is behaving like a camp leader - getting on with things and taking people with her."
"Virgin Radio is a perfect fit," Manning adds. "Her background at Capital and her time at Yahoo! will help. Virgin Radio needs more energy and dynamism but it is a great brand and Fru is good with great brands."
Another agency source says of Hazlitt: "She's egocentric in a very nice way - a magnificent presenter, an old-style media person. There's a danger she comes across as a luvvie, but she's a genuine luvvie."
Nikki Mendonca, who is now the business development director of Omnicom Media Group in Europe, worked with Hazlitt for four years at Capital.
She says: "She has an enviable way of getting what she wants and uses the sheer power of her personality to get around people, especially difficult, intransigent old men." Mendonca also says that Hazlitt has exceptional people skills and "is driven by a genuine interest in others".
"She is determined, ambitious but not ruthless and she is not afraid of carving out new paths," Mendonca concludes.
Hazlitt has already made some changes, among them bringing in Nick Hewatt as Virgin Radio's sales director. Hewatt is charged with replicating the success Virgin has had with sponsorship in the traditional airtime market.
"Where we haven't built a good case before is where we can become mighty and relevant in the airtime market - this is one of Hewatt's strengths," Hazlitt says.
She is hoping the introduction of O'Connell, the former Xfm breakfast host, will increase Virgin's 3.2 per cent London share and its national reach, via its AM licence, of 2.5 million. Hazlitt argues he has the warmth to get close to an audience and develop top promotions to bring in new listeners. "Listeners adore him, he's very funny and is known for doing ridiculous things. The only issue is awareness - he's not a celebrity but people should feel they have discovered him."
Despite Virgin's commercial rivals, it seems O'Connell has a different target. Hazlitt says: "To be honest, the guns are trained on Chris Moyles (on Radio 1). Christian's will be a novel breakfast show - cutting-edge and powerful, doing what great radio should be doing."
So how useful is her online experience? Hazlitt says: "We have to be platform-agnostic. Who cares about what platform people will be listening on in ten years? They will not be listening on analogue radios but the issue is to be broadly digital, so wherever listening habits evolve, we will be there."
With this in mind, Hazlitt has harsh words for some in the industry: "To be honest, I don't know why people bother applying for analogue licences. There may be a quick buck involved but it's crazy."
Hazlitt is focused on making Virgin a major radio player, but in addition to the public speaking (an outlet for her acting talents that flourished in an early career before she moved into advertising), she is also a keen runner. Since the birth of her twins, the single mother with an unconventional home life has had to put running marathons on hold, opting instead for a treadmill in her kitchen.
The only time she sits still is when catching up on EastEnders at the weekend, so she may have the dynamism that Virgin Radio so needs.