Martin takes advice from Bono and Stipe about not being a 'd**k'

Chris Martin has to "work really hard" not to "be a d**k".

The Coldplay singer admits it can be difficult being an arena rock frontman as "only about 20 other people do" it, and he has relied heavily on "key peers" Bono and Mickael Stipe, from U2 and R.E.M. respectively for advice over the years.