By Seamus Duff Nicky Campbell broke down in tears live on air while speaking to Karen Jolliffe – one of the many victims of the Post Office scandal. The 62-year-old presenter was speaking to 77-year-old former post mistress Karen on his BBC Radio 5 Live show – which is both transmitted through the airwaves and broadcast via video link. Karen is one of more than 700 sub-postmasters who were wrongly convicted of false accounting after Horizon, a computer program they used to calculate their accounts, became defective and counted a loss when there was not one, making it appear that there was cash…