Mystery characters appearing in KMail, Konqueror and Akregator Fedora 7 and KDE

[Peter Reed]

Every 15 seconds or so mysterious letters in little boxes show up on a 
displayed page, email or news feed in any of the above applications.  They 
seem to appear above links only and last on the page for 15 seconds or so and 
will return again in the same time period.  If I push the ctrl button it will 
turn the characters off but again will return.
My question how do I stop these character boxes from returning permanently  
because they are driving me nuts.
Thank you
Peter