I have some Google referral ads on my site but then I wanted to change them. I logged into Adsense and chose a different advertiser but I still have the same ad displayed
You did update the code which is on your site. Correct? If you did, view your site with a proxy, it will have the dns stuff updated and you will view the latest version of the site.
Just to make sure, you have to change this part in your code. I erased your pub id and cpm choice just incase
Well i am also facing that issue and many others. Since yesterday its displaying any ad (chosen randomly) but not the one we chose. Basically its forcing a "Best performing ad" to the select code even thought we kept it uncheck.
upper its a issue and nothing to do with cache. I did everything i could. If you are using referrals, you might have noticed similar pattern. I guess this is happening for international publishers and not for US pubs