Ok, need some suggestions as to what MIGHT be wrong here. Not much info to go on, but see what you make of it.
I have a laser projector, RGB. It will run under DMX control. I can only get 4 colours out of it rather than 7 though: blue, cyan, magenta and white. If any of the diodes are on, the blue is on. This behaviour manifests in the laser's demo mode, too. What might cause this?