Sorry I was a bit vague.
This action is used on 50+ models.
If I remove the random_seed(0); I get the same result each time (their skins will randomize, but always be the same random value [as the manual says it would]).
with the random_seed(0) all skins stay the same color.
@xbox: yes, its been defined

@malice: I tried your idea, but it didnt work

I've done this before in the past and it worked fine. Strange how such a thing can happen..