The former Gnarls Barkley star has...
The singer has now conceded he is working too hard and has decided to leave Rihanna's tour.
A spokesperson for the Forget You star tells Gossip Cop, "He always puts 100 per cent into his work. With the requirements and time commitment to The Voice, on top of heading back into the recording studio and an upcoming book, he feels that he wouldn't give his fans the show that they deserve."
