XF 1.4 Current visitors issue

This feature doesn't diplay correctly on my forum.
It multiplies the numbers of visitors, every time i visit another page. So if i visit 10 topics, there are 10 members online : 10 times my own name.

I imported from vBulletin, everything is fine except for that... I am the only one online and there are 10 visitors online.

So basically instead of having one IP = one visitor, it counts one visit/a page = one visitor.

I rebuilt cache for everything, it doesn't help.

Do you have any idea ?