Ok the product is deffinately set to priced by attributes

Im not too sure what you meant by "For attributes, consider the settings for at least: Default and Base Price."

all the attributes in both colour and size are set to Display only X ,Free O, Default X, Discounted O ,Base Price O,Required X
(this where a screen shot would be handy if i could get one into the post)

I have tried turning the defaults on and off, setting all but one to either x or o,with and without setting free to x or o
I have also tried setting the priority of the options so that it did size first, with exactly the same result