Pixies rocker Black Francis is baffled by the furore over the band's changing line-up, insisting: "It ain't that big of a deal." The Velouria hitmakers are now working with their third bassist in less than six months after recently firing Kim Shattuck, who replaced long-term member Kim Deal in the summer (13). The Muffs star Shattuck told how she was left shocked by the surprise sacking last month (Nov13), and rumours about her departure are swirling among fans, but now frontman Francis has spoken out to insist it is all part of life in a rock band. He tells Yahoo Music, "The big question mark is, if it was going so well, why are you changing it up again? I guess it's a fair question, but what I would say is, just because some shows went well or a recording session went well with somebody, that doesn't mean that now you guys are married and this is forever. It's not really how it works when you're a band. And it's hard to explain to people, especially if they get emotionally attached to one person... "Frankly, you don't want to explain it to anybody - a lot of it's personal, private s**t. It's like politics and sports and people's personal lives have all been smeared together in this modern world. It's a very presumptuous attitude about a lot of things. (People say) 'Oh you're shifting something in your world - we demand a statement as to why'. "I'm not the mayor, this isn't the bus service for a town. This is a rock band. There's been a shift in the line-up, big woop-dee-doo... as far as we're concerned it ain't that big of a deal."