ah yeah that old chestnut of corrupt scenes, good luck in isolating the cause again !
so in your hunt for live operators did you try Brad's plugin 'Sanity check' ? https://groups.google.com/forum/?fromgroups#!topicsearchin/xsi_list/group:xsi_list$20AND$20subject:sanity/xsi_list/FmE0agPe6d8 damn useful have to say in cases like this. and interesting what turns up :)
