menu not showing in the correct position

hello all
i have installed coffe 2.5 template, showing well in chrome and safari, but when i open it with firefox or internet explorer, i see the menu with a big space up. i attach 2 images, 1 showung correct in chrome, and the other with firefox.

printscreen-firefox.jpg

printscreen-chrome.jpg

any help would be great!
thank you all in advance and best regards,
have a nice day,
Sergi,

i just solved by disabling the sign in module in right top home page.
regards,