Area Shape Map question
 

Hi guys,

I am using an area shape map to designate cooridnates on my page for my tabs. So that when I click on the tab "about us" it will go to the about us page and when I click on "contact us" it will go to the contact page etc..... For some reason when I click on them the page that I am currently on will jump like 1 cm or something. Does anyone know why this is? Every page that I am on does it. Every time I click on one of those links, the page will jump just a little bit. It's not much, but it is enough to drive me crazy.