For some time, I have notice that my Google adsense advertising do not appear on certains pages of my blog. I am not worried and I have attributed this oddity to Google. I have decided today to explore the reals reasons and I found the culprit. This is Cloudflare and more specially the option « Rocket Loader ™ (Web Optimization) ».
As a reminder, the feature is in beta. It is therefore not surprising that there is some recurring bugs.
Edit : Confirmation by Cloudflare :
Settings->CloudFlare Settings->Performance Settings->Rocket Loader->Toggle Off.
Note: We would also strongly recommend installing mod_cloudflare so original visitor IP is passed back to your server logs. »