The UK's regional accents are changing - and it's not just the spread of Estuary English behind this shift, but the slang and intonation of Caribbean and Asian voices.
Let me start by declaring an interest: I've lived in London for 15 years and know the city as well as any local.
But as soon as I open my mouth, it's obvious that like the most recently arrived Polish plumber, I'm not from round these parts, as they say in Greater Manchester, where I was born.
Even my four-year-old son can spot it: "It's glahss - not glass, Daddy," he helpfully points out.
I may have moved south, but like my former neighbours who chose to stay in the north of England, I've steadfastly refused to accept the advance of the elongated southern vowels that remain the most recognisable indicator of where your roots lie in the UK.
As the British Library launches its Sounds Familiar website to help a growing number of youngsters studying our linguistic differences, I cannot help but feel a stubborn pride in resisting the rising tide of so-called "Estuary English" that has spread out from London across southern half of the country.
Am I bovvered by its spread? Many are. But perhaps all is not what it seems, says Jonnie Robinson, the man behind a British Library scheme to get a new generation of speakers to contribute to an online collection mapping the way we speak.
"I'd accepted the line you usually hear that dialects and accents are disappearing," he says. "Yes, things are changing as they always will, but the diversity is still as wide as it ever was."
True, some of the old regional accents have been pushed out. Mr Robinson cites that of the entertainer, Pam Ayres, whose distinctive voice many would place as coming from somewhere in the South West. In fact, recordings in the British Library's archive show it as typical of rural Berkshire where she was born 50 years ago - just a half hour's drive from Heathrow Airport on the western edge of London.
That accent, and the received pronunciation of the Royals encamped at the other end of Berkshire in Windsor Castle, may be rare. But in Reading, between these two extremes, there's a new accent with influences from Commonwealth immigrants from the Caribbean and Indian sub-continent.
"Those cultures are leaving their mark on the language just as the Viking settlers did when they dominated Yorkshire hundreds of years ago," says Mr Robinson.
British Library has put 5,500 recordings of accents and dialects online
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Received pronunciation - or BBC English - is a minority accent spoken by no more than 2% of people
"What we're hearing are wonderful new voices with vowel sounds from places like Jamaica and Asia mixed with more familiar accents. Take the boxer Amir Khan. If you close your eyes and listen, it's obvious he's an Asian lad. But at the same time he couldn't be from anywhere other than Lancashire."
Among the first to contribute to the British Library's new site are from Holy Cross Sixth Form College, just down the road from the gym in Bury in greater Manchester, where the Olympic medal winning boxer used to train.
They are among the 35,000 teenagers studying at any one time for an A-level in English language, which involves work on accents and different patterns of speech. It's the fastest growing course at that level.
"It's something the students are really, really interested in," says lecturer Rosie McKelvey, who is helping record their voices for the project.
"We've got students from north Manchester right the way up to Rossendale in Lancashire, and many don't think they've got an accent - until you ask them to say 'bus' and straight away you can hear all the different pronunciations."
And Ms McKelvey, who moved to the area from her native Liverpool 15 years ago, knows just how much accents still mark us all out.
"I was on Bury market at a florists' stall the other day and the woman was amazed. 'And you come all this way - just to buy your flowers,' she said."
Getting people to record their own voices will also overcome another problem researchers into dialects have faced, says Jonnie Robinson.
Many of the recordings at the British Library date from the 1950s and 60s, when people seemed a lot less aware of how local the language they used might be. Radio, and the omnipresence of TV, have changed that.
"Someone in Newcastle may well say 'baby' rather than 'bairn' to an outsider now, because they know they may not be understood otherwise," he says. "A Mancunian will say the 'narrow passage between the houses' rather than use the word 'ginnel', even though they'll still talk like that with friends and people they feel comfortable with."
The project will also mean the British Library is able to gather samples of how younger people talk - a group historically under-represented in studies into accents - and that may give an insight into how the voice of Britain will change in future.
"I sound a bit like my father, but not the same," says Yorkshire-born Mr Robinson. "He sounded a bit like his father - but different too. We're all part of this process of change."