Last couple weeks, all my different pages have basically the same adsense
ads, (cane) using the main keywords. The ads USED TO BE, a lot more page specific , (defence cane, redhat cane, pimp cane,etc.) Revenue has fallen.

I must of done something wrong, is there any way to get MORE VARIED ads back?

Maybe this relates to other threads about recent adsense account pattern changes.

Some people have noticed that different ad sizes and even the placement of ads has a lot to do with what ads are displayed - crazy, isn't it? It's always a good idea to have your adsense code above site navigation in the HTML code ... this way, it's not getting a mix of completely unrelated links that appear on all pages of the site. For example, suppose near the top of my page I had a list of all of the forums available, and then AdSense right below that ... AdSense would get confused what the specific page was about. Hope this helps. Good luck! It's really just a matter of luck with AdSense I've found ;)