Live Nation's Andy Copping knows all about dealing with grumpy customers direct. The man responsible for booking hundreds of acts at Download Festival in the past 10 years - including the 148 artists playing at the event this weekend - boasts over 14,000 followers on Twitter; and they're not shy in sharing their opinions.

"It's great when they're saying the bill's great, but you've also got to deal with it when they're disgruntled," he says. "You wake up in the ...