Sir Paul McCartney is disappointed by the rise of the MP3 player - because it stops listeners interacting with nature. The former Beatle admits he's not a fan of portable music devices, as it reminds him of hard work in the studio - and believes headphones shut people off from the world when they should be enjoying the world around them. He says, "Headphones remind me of work - whereas for most people it's the opposite. "The thing is, you get sealed off from the world, and that's fine when you're making a record. But, when you're actually just walking around, you're gonna miss birdsong, and that's so special. But his hatred of headphone-based music doesn't extend to that performed on a guitar: "Guitars are different. It's a very embraceable instrument - even looks like a woman."