U2 frontman Bono has apologised to fans for invading their iTunes library, saying they "might have got carried away" with their album giveaway.

In a filmed question and answer session on Facebook, the band answered questions from their fans about their friendship and music.

But it was to Harriet Madeline Jobson's question that Bono gave his revealing answer.

"Can you please never release an album on iTunes that automatically downloads to people's playlists ever again. It's really rude," she said.

Looking sheepish, the musician answered: "Oops, I'm sorry about that. Um, I had this beautiful idea...might have got carried away with ourselves. Artists are prone to that kind of thing."

Bono could have stopped there, but he continued with his mea culpa, which seemed to provide some amusement for his fellow band members.

"A drop of megalomania, touch of generosity, dash of self-promotion and a deep fear that these songs that we poured our lives into over the last few years won't be heard, there's a lot of noise out there."

"I guess we got a bit noisy ourselves to get through it."

The rockers made their surprise announcement last month at an Apple unveiling event, but it was met with wide criticism. More than half a billion people had Songs Of Innocence automatically downloaded to their iTunes libraries.

Twitter user @EricAmer wrote: "Waking up with the new U2 album on automatically installed on your iTunes is like waking up with a pimple in the morning. #nothanks"

On Monday, Iggy Pop slammed the band for the move, saying they had stolen the listener's choice to buy or download music.

Apple created a special tool which allowed users to delete the album if they wished.

Watch the session below:

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