Irrelevant adsense ads and possible causes

Most probable reasons for irrelevant ads: 1.The name of the site having nothing to do with the main theme of the site..In my opinion when Adsense cannot determine page content it starts reading the domain name for a clue, for serving Adsense ads.I feel that one of the best ways to avoid irrelevant ads on your site,is to ensure that you select the domain name that explains the kind of content that you intend to carry on your site.Adsense does take this into consideration. 2.Very little or no Content or content containing less number of keywords.Adsense ads are contextual based.It is what you write that determines the ads served to you.3.No keywords META TAG or irrelevant meta tag keywords.(Some may argue that Meta tag has lost it's relevancy,but based on my own experience i would say that it is still relevant)4.The google mediabot might have been blocked by a robot's txt on your site.Unless this bot is allowed to crawl your content you will not be getting any relevant ads.How TO CHECK>>Log in to your adsense acccount>>>"Site Diagnostics"See if your URL is blocked.If blocked,look for the link :"Google Webmaster Central".On the page that follows click"Use our site status wizard">>>Enter your site URL>>find out when the bot crawled your site,follow the instructions after going to webmaster tools from that page. 5.Assuming every point i have mentioned above has already been, taken care of,then you might have just pasted your ads.In which case pls wait for a few days for your adsense ads to become more relevant.5..As regards the refferal ads choose the smallest possible size for your selected refferal to show.