I have a similar problem with LED lighting-- i will try to explain. I have a new setup in a youth church building. We have puchased 8 Chauvet LED slim ( par 38 ) 2 regular par can lights with bulbs and 1 dmx4-led dimmer pack. we have all of the lights hooked up to a obey 40 board. All of the leds work perfectly with out going through the dmx dimmer pack ( which we have so that we can run both the par can lights and also the LED ones with the same board ) when we hook up the DMX dimmer in our system the led lights begin to flicker and jump around. the can lights work fine with the faders on the obey 40. All of the leds are assisnged to the right channels in the board to make them come on. my only guess is what maybe this dmx dimmer pack does not work with our system? it has both the DMX in and DMX out. Im lost and any help would be appreciated.