Smartpack dimmer behavior inconsistent across channels

Hi there - we are using a 6Ch Smartpack portable and are running into an issue where Channels 3 & 4 are behaving differently than the other channels in that they are dimming differently. We have checked the dimmer curves and all are set the same, done a deep system reset and no difference in behavior. The issue is persisting with 2 different consoles (a Nomad/Gadget 2 combo and a simple LSI board). We also have set the intensity on the dimmer directly and find that the intensity difference persists the same as when it is connected to a console. 

As a result we are pretty sure it is something with the dimmer itself but are wondering if anyone else has come across this behavior and how it was resolved.

Thanks in advance!