2 Brand New MSD Dist's only advance 8 Deg

Hey,

I just bought two MSD Distributors, both are giving me 8 degree off (under) advances equally with all the stops. WTH??? I don't know how this can be. Any tips, or things I can check? The two are identical, but one black cap and one red cap, as per link below. The red is in it now.

I'm using factory EI set up, could this be the cause?

MSD Billet Distributors 8534

Thanks