Giberish characters after saving Post

Hi,

After i add content and save the post, plan english text is being converted to some giberish chars. i have first seen this today and i later updated to 3.3, however the problem still persists

here is the site URL: http://www.pm-consultinggroup.com/battlefield-3-review/

Also, the same is happening with other WP sites of mine

Can anyone pls suggest a solution