In the past couple years there have been three viola hires, a bass hire, and a title chair violin. The committees vary based on the instrument which of course you know, but in the case of reannouced auditions after no-hires, a lot of orchestras have archaic by-laws which force the same (failing) committee to reconvene for the next go at the same audition. Politics can play into who gets auto-advanced, and if there is a screen down in final rounds there is a huge possibility of nepotism.