Not sure whose issue it is but I had 2 Thaumcraft 6 items in my baubles slots (offhand and Belt) with soul-bound on them. I died and it seems to have deleted the items. I tried restoring inventory and checked the death list and there is no record of them. I have another item from Thaumcraft 2 in my head bauble slot and it seems to be fine (I think because it doesn't have soul-bound on it).