Page background image
 

I'm trying out a new Style and one with a background image, which I've never used before.

I've set the background image under 'Page background' in 'All Style options' and on the homepage and the forum pages it looks fine but when I go into the threads it randomly cuts out and then starts again. The only way I can get it to display as one continuous background is to put it as fixed, but this isn't what I want to do.

I've attached three images which show how the background randomly stops before starting again.

My background image is here which shows that it isn't a problem with the image as no pictures touch the top or bottom ends.

What have I done wrong & how can I correct it?

Thanks