Frank Farian, who has died aged 82, was a music producer thought to have sold more than 800 million records; he was the brains behind Boney M, whom he guided to pop superstardom with a string of hit singles around the world, many of them written by him; but he was also the brains behind Milli Vanilli, whose career imploded when it was revealed that they had been lip-synching rather than singing their own vocals.