Sub navigation not functioning properly

[ubuntusurfer]

Hi, I am working with the theme Rustik and their support has been pretty lackluster. But luckily there's SitePoint, right?!

Anyway, I am having issues with adding a subnav to my main menu. I am using the built in WP menu editor. On the homepage, the subnav is not hiding like it should. However, on every other page of the site, it is. I can't for the life of me figure out why it isn't working. Anyone might be able to steer me in the right direction?

You can see where the issue is here.

Thanks in advance for your help!!

[interfinet]

I have checked the site. I don't think its essential to change. On hover to menu with submenu "ul li" display and display time is ok.