It has to do with your default encoding settings, which are under View. I think you have to change it to Unicode (UTF-8). There's also an issue with Languages, which is under Tools - Options - General. I think you have to set your Language to English/United States [en-us]. It's a problem that seems to pop up under pretty much any browser. I sort of like it, so I never bothered to check my settings. It's more fun than actually looking at the ads.
I was just playing around with the encoding settings, and discovered they can be set to different settings in different tabs. I think they are set by the webpage. I'm not currently having the problem (new laptop) so I can't really test it. But that's what worked before my old laptop bought the farm.