WordPress Bar Disappears

Hello there,

I have a very annoying problem when I’m using the plugin:

Many times I “lose” the admin bar on top of the site, if I am browsing the pages. The solution is to login again, clear cache, and then it will work fine for the next page I view. But after a few clicks, I will lose the bar again. So I need to go back and forward all the time to be able to see the admin bar.

Any way to resolve this?
thanks

The page I need help with: [log in to see the link]