It was a giant adsense malvertising attack, that they went on to fix.I have never had that happen here and I use an iPad or iPhone 100% of the time (here). I set up my bookmark to start me in level 2, not sure if that is why I'm not seeing the issue. Worth a try.
On other sites and some apps this is a problem because of the order in which a page loads. The redirect link loads prior to the page images, so I'm accidentially hitting a redirect link when I'm trying to do something else. In many cases it can be solved by page layouts that put links far away from ads.
Reread the OP and looks like that isn't the issue. Hmm.