Nice Menu 1st top level Item in the list will not expand it's childs, works fine for the rest.

Getting a very weird behaviour from nice menus in a site. When using nice menus I notice that all the child items expand from the 2nd father item downwards in the nice menu list, but not from the 1st father item. By father item I refer to the Top level item.

Wonder what could be causing this. The menu is based on taxonomy terms and the module taxonomy menu has been enabled. So basically the nice menu is based on taxonomy terms with child elements.

You can see this in action visiting: www.trazarte.es

The menu is located on the right hand side below the ebook link and this site is built in Drupal 7.