Right i am giving this another go. Its seems after a re install that it does not conflic with the other ad on (rotating ads) yay!
I am however still having an issue when no ads are displayed at all.
This is my site www.windowcleaningforums.co.uk
The ads i have are a header banner ad
a top of sidebar ad
a footer below content ad
ad in profiles above messages
below sticks ad
These are a mixture of both static image ads and adsense. If you refresh the page a few times and click around the site you will notice that on occasions no ads show at all. Its noticeable with the top ads above breadccrumbs and top of sidebar as they are visible right away at the top of the site.
I have just done this video to try and show what i am on about @Jake B.