While the Arab world is used to being rocked by car-bombs and mortar shells, it is less accustomed to rockers of the musical variety - punkers and metal-heads - who like to shake things up with their lefty lyrics and alternative attitudes. Sectarian clashes and rage against the regime might be par for the course, but rock bands with a cause to croon about present quite the challenge. Changing their tune From deeper underground, a new wave of bands with a battle to wage are breaking the surface and not ...