I have having the same problem as this post: "@font-face conflicts with drop down alignment", which was closed without being resolved.
(I also tried following this thread's solution even though it's not exactly my problem, but I'm desperate. It didn't work anyway. "Problem with generated CSS for class="sub-container non-mega& ").
I am linking to Google web fonts in my head, for example:
<link href='http://fonts.googleapis.com/css?family=BenchNine|Anton|Roboto+Condensed:300italic,400italic,700italic,700,300,400' rel='stylesheet' type='text/css'>
Most of the time the jquery mega submenu positions itself correctly. I have it set to top: 0; and left: 0; The problems seems to occur when the page is initially loading, and the mouse happens to be hovering over the nav menu before the page is loaded. Once the page loads, and you hover over a nav item with a drop down, the drop down is way off to the right. Anywhere from 24-119 pixels off.
This happens in:
Mac - FF, Chrome, Safari
PC - FF, Chrome (IE amazingly works fine)
I tested this by removing my link to the Google fonts, and repeatedly refreshed and moved my mouse around the menu before the page loaded, and everything worked fine; the submenus were perfectly positioned. As soon as I placed my link back to the Google fonts, the problems happened again.
I really love this plugin otherwise, I hope I don't have to find an alternative. My deadline is in 2 days, so I'm probably going to have to unfortunately.
Thanks for anyone's help in advance.