Error displaying In Post Ads

In post ads are throwing up a line...
"class=”wdca_ad_item wdca_not_placed wdca_custom_ad “
> "
before displaying the ad.

As well as this unwantd text the error also affects the div nesting and the rest of teh page layout.

I have only just noticed this recently. It was working perfectly when I installed it first time.
I'm not sure where to start on a solution. Any ideas?

See any posting page on the site e.g: