In 2010, Adeleye was working as a care worker prior to taking part in the seventh series of The X Factor and was one of the 16 finalists for the live shows starting 9 October 2010. He was eliminated on 24 October 2010 after week 3 of the live shows, finishing in twelfth place.
Adeleye started singing in the Royal Borough of Kensington and Chelsea Choir when he was 14 and moved on to giving private singing lessons, including to Oritsé Williams from the boyband JLS. He also took part in a number of theatrical works.
In 1998, Adeleye decided to leave the theatrical environment that he loved so much, and focus on music. He formed the duo Nu-park with Shad, a fellow young artist. The band was further expanded to become a five-piece band.
Professionally Adeleye worked as an activity co-ordinator at Forrester Court care home in Westminster, helping people with early onset dementia for two years.
After the disbanding of Nu-park, Adeleye continued as a solo artist writing his own material starting in 2001. His first important break came when one of his own compositions entitled "Soul Glo" earned him in 2003 the UK MOBO competition award in the London venue Sound. As a result, he was signed by record company Universal-Island and artist management company Shalit Global (owned by Charlotte Church's former manager Johnathan Shalit). He began writing with many industry names such as Brian Rawling, Lamont Dozier, Guy Chambers and Lisa Stansfield.
During this time he began doing public appearances on televisions shows such as ITV's GMTV and BBC's CBBC. In 2004, he toured with UK artist Jamelia. In 2007, he collaborated with DJ High Contrast and was featured vocally in two of the songs on High Contrast's album Tough Guys Don't Dance, namely "Forever and a Day" and "Eternal Optimist".
In 2008, J'Nay released his EP Merry Go Round containing five tracks. On the show Britain's Next Top Model, he was tasked with picking models to dance with him on stage using one of the tracks of Merry Go Round. He later split with both his record company and his management company for reasons that are unknown.
In 2010 he entered the seventh UK series of The X Factor using his birth name, and was one of the final 12 contestants. In auditions, he sang "You Are So Beautiful". At the judges' houses stage, in presence of judge and mentor Louis Walsh and guest Sharon Osbourne, he sang "Billionaire". However, Adeleye changed the lyrics from "billionaire" to "millionaire". Walsh picked him as one of his final three in the category of Over-28s. In the third week of live shows, Adeleye was one of two acts receiving the fewest public votes and was in the bottom two along with Treyc Cohen. Three of the four judges then voted to eliminate Adeleye.
John Adeleye performed the following songs during the contest:
After his elimination, Adeleye told The X Factor host Dermot O'Leary that he would start writing material for a possible album.2003: "Soul Glo"
In High Contrast's 2007 album Tough Guys Don't Dance, J'nay is credited with two of the album's 13 tracks:Track #5: "Forever And A Day" (High Contrast with vocals by J'nay)
Track #10: "Eternal Optimist" (High Contrast with vocals by J'nay)
J'Nay track "Soul Glo" appears in the album MOBO Presents Urban Beats 2003, a compilation of MOBO participants and winners for the year. J'Nay's is track No. 18 of the 40-track 2-disc release by various artists.In 2003, as J'Nay won Music of Black Origin Awards MOBO award for "Unsung Artist of the Year" (reserved for unsigned artist)