We have a website that has been live for 18 months, and all of a sudden doing a wacky thing on the internal machines. If you roll over the first menu item, the submenu goes under the 2nd menu. You can't even get to it, because by the time you move, it disappears.
The website is www.7thwavelabs.com
On the Pic1, you will see how the menu is incorrect.
On the Pic2, you will see how it looks proper.
Why is this doing this on just a few machines?
I personally have tested it on 8 different machines with Windows 7, Windows 8, Mac, and a combination of IE, 9,10,11, Firefox and Chrome. It looks fine for me.