The Nashville Symphony has been hitting many high notes recently. But one little bit of dissonance: “Mary Kathryn Vanosdale, the NSO’s longtime concertmaster, was forced to sit out the 2006-07 season because of an internal dispute.” But she “recently prevailed in a private arbitration case, and so she will reassume her old post as head of the first violin section starting in September.” So what was the beef? The musicians are speculating…