Multiple rating fields (while viewing) widget changes all ratings

I have multiple fields on a node which allows people to give a candidate rating on several different categories, e.g. 'Timeliness', 'Honesty', that sort of thing.

I'm finding that when viewing the node and using the ratings widget for any of the fields, it updates all the fields at once with the value selected. It appears as though the Ajax is updating all ratings fields on that node, not just the intended field.

Seems like a fairly major problem, any ideas?