I would say you have a
processor problem
You probably already know this but the sequence in these is
When
Power is applied the red light goes on
If there is no control signal present, then all of the yellow indicator lights go in and the outputs are set to full on
when
Mpx is present then the green control signal light goes on and the outputs are determined by the mxp xontrol packet that has been sent
These
unit supply
power back to the control board which can be powered from the
dimmer packs instead of their own
power connection, but the higher end boards have their own
power system
I have found that typically if it is a problem like a defective
dimmer cirsut then it typically only takes out on e set of two outputs, I know you said you checked the fuses so they should be ok and if everything meters out ok then it usually is a logic/
processor issue
NSI is good about fixing these on a
flat rate basis and with pretty good turn around.
I'd
send it back
Sharyn