thank you. I followed these directions and the second controller appeared int the interface as controller 2. I was able to configure the extra fan by switching to controller 2 in the software. Everything was working as expected.
After a restart, however, I got a warning controller 2 error, and the controller 2 icon is now red in the interface. I can't change the fan's colors anymore, just the light pattern, and when I try to save a profile, the fans on the original controller change color, or shut off, at random.
Not sure sure what I should do! I tried unplugging everything, restarting, plugging back in, restarting, still the same issue.