Printing only part of a page: intermittently

I'm printing photographs on a Canon Pro10, using borderless options with a photo size to fit on the page (A4). 

Sometimes the page comes out with only part of the page printed, even though the preview on the screen shows the whole page picture. I suspect that the system is keeping a previous smaller size setting. Today I printed  an A4 picture but only the 10 x 15 middle part printed. If I try again, the second or third one is correct, but this uses a lot of ink. 

I'm using presets for the different sizes.