setInterval

I used setIntervals calling functions to make this menu

[url=“http://www.maridesign.com.br/mari”]www.maridesign.com.br/mari

[url=“http://www.maridesign.com.br/mari”]
I’d like to know why those intervals start at normal speed, and after a lot of clicks in menu buttons, the functions are called with a larger interval

if you click “portifolio” button, it’ll clean all the others intervals…and the same thing if you click “agencia” button, and “contato”

what can I do to solve this problem?

thanx
Chan