Bruno Marshas said that record lables struggled to know how best to market him due to his eclectic sound.

He says his style of musi, which does not sit in a specific genre was the reason it took him so long to secure a record deal.

The 'Locked out of Heaven' singer said: ''That's been the struggle since I started. That was why I couldn't get a deal, that was why a lot of record executives said they didn't know how to market me, because who do they market it to?

''Is it young fans? Is it old fans? Is it urban music? Is it rhythmic music? Is it pop music? Is it rock music? They didn't know what lane they could push the brand to.''

Desite his wide range of influences, the 27-year-old said he prefers the sounds of his second album, 'Unorthodox Jukebox' to his debut 'Doowops & Hooligans.'

He added: ''Being influenced by doo-wop on my first album - with classic love songs, 1950s.

"I have a passion for that era. But that's not everything that I listen to.

''(The new album) is more of me. This album is more the whole of everything I love, the music I love to dance to, the music I love to listen to with my girl. Things that I want to say that I've always wanted to say.''

Watch Bruno Mars perform Bruno Mars' 'Locked Out of Heaven' on The 'X Factor' USA below: