Hi @nilo, whilst the Tobii Core Software does recognise multiple trackers connected, I am afraid only one will be active at any one time.
Since our trackers are based on infrared light, having two trackers running simultaneously would interfere with each other and cause trackability problems.
Unfortunately, there is no interface for choosing one tracker or the other, but the rule is that:
-External trackers are selected before built-in ones
-The latest connected tracker is selected
-On boot the last used tracker is selected
Accordingly the use of multiple trackers is not an officially supported platform. I therefore wonder if your connection issues persist when only one tracker is connected? That would seem the most appropriate point to start investigating. Please let us know.