I'm leaving a slightly different issue here, tho the subject line is pretty much the same so figure I won't make a whole new post.
Sometimes when my chars initiative is "tied", represented by intertwined portraits at top left in combat UI, the system will end turn for each of them after the first one goes. So if Gale and Shadowheart are bound up, I sometimes have Gale do a thing, end his turn, and Shadowheart gets skipped.
This *may* happen (more?) when I click in to Shadowheart before ending Gale's turn, but I'm not positive.