R&B singer Ne-Yo has taken aim at stars who lip-sync during their concerts, insisting they don't give fans value for money.

The So Sick hitmaker is adamant he always sings live and he can't stand seeing performances by artists who mime along to a backing track.

He says, "As an artist, you need to learn to sing or dance, or sing and dance at the same time. That's your job. You can't be a mechanic, but let somebody else fix the car... The same thing is true about being an artist. If I want to hear what you sound like on the Cd, I'll just listen to the Cd.

"If you don't... sing so well, or dance so well, and you need a bunch of pyro, smoke and mirrors to cover up that fact, I have an issue, because I'll feel like I haven't got my money's worth."