Not sure if it is a Mixer bug or a Super track issue. I have observed it when working with Super tracks.

Example:
1 Set strings track to a Super MIDI patch
2 Select a VSTi as the source instrument
3 Pan the Super MIDI instrument
4 BUG: adjust the pan of any other instrument (via the Mixer) and it will adjust the pan of the VSTi as well.


Studio One (latest version), Win 11 23H2 , i9 -10940X 3.3 GHz, 32GB Mem, a 4K 40" monitor, PreSonus Studio Live III Console as interface/controller. secondarily test on Reaper, Cakewalk, and S1 on Surface Pro 3 Win 10 (latest versions).