I have inserted the code for my mobile site a couple of weeks ago, and it’s not showing up in almost all of my tests. The only browser It’s working on is Chrome on Android (tested on Galaxy S2). It’s not showing up on iPhones, tested both Safari and Chrome on several different devices.
The site is http://m.radicalislam.org
I’ve looked at this article, and couldn’t find any applicable solution
My first step into debugging this issue would be to set the option in Adsense to show a backup ad of a solid colour e.g. Blue or something obvious. This will give you a clue as to whether there is an issue in displaying anything from Google, or if it is an issue specifically with Google serving you adverts.
If the blue colour doesn’t show, that might be a good thing, as it could just mean there is an issue with your code (maybe a conflict with all the page speed stuff you’ve got going on?).
If it does show, then that means Google isn’t serving you ads. There’s a number of reasons as to why that may be: https://support.google.com/adsense/bin/answer.py?hl=en-GB&answer=75764&topic=2453404&parent=23384&rd=1