That firmware update is probably required, but unfortunately, I don’t have any details on whether that upgrade will cause any incompatibilities with Tobii Studio. It was probably released 10+ years ago (That tracker was old already when I started at Tobii 12 years ago). I’m pretty sure that the last major release of Tobii Studio (3.x) should be compatible with the latest version of the X120 firmware, but I’m not able to guarantee that. And if you haven’t updated tracker firmware in 10+ years, chances are that you are also on an old version of Tobii Studio.
The device I have is running on FW 2.0.7 but I don’t have Tobii Studio installed.