Thank you for responding so quickly, Jonah.
I’m running 2.0.11 and I have no other plugins installed or activated on my site. I haven’t made any modifications to the plugin templates. I have the “Responsive” theme activated on my site, but I haven’t made any modifications to things other than changing the color in the CSS.
My list.php is here for viewing.
My site is here in case you need to see more.
Just to make sure, I activated the “Twenty Twelve” theme in WP and I still have the same problem, so I don’t think it’s something to do with the theme I’m using.
Thanks!