SalesIQ visitor not leaving

Since this problem is still active and the other forum topic is marked as "solved", I wanted to make this new topic.

Problem: In SalesIQ under "Visitors online", visitors often don't disappear and just pile up. When I want to initiate a chat, the visitors appears to be offline and are finally removed form the list.

Yesterday I had around 30 visitors showing as "on site" for over 2-5 hours. This is annoying and makes it hard to find real active visitors.

This of course screws with the "visitor time on site" statistic as well I suppose, which is an important indicator and should reflect the real time on site.

Please look at this problem. Thank you in advance.