This is due to different lengths of foil remaining on each of the foils and is a design flaw in the Gerber Edge.
in addition to the more comprehensive solutions Fred indicated, you may wish to compare results by trying some other foils. Let's just say it was black & white colors, printed on clear... and the black foil was a brand new 50yard foil, with nothing used yet, but the white foil was a 50yard foil that is almost all used up. The different diameter of remaining foil on the roll on the in-feed side of the cartridge, results in the slight difference in where that black print & the white print land on the media. So, you could swap the nearly consumed white foil, with another color that is new, and confirm if that resolves it. Then of course if it does, using a new roll of white would also be a solution for the issue.
Bill's idea I suppose would have varying degrees of potential, relative to how complex the artwork is, or how tight the registration is, or just exactly where, how, & how often the two colors meet. Maybe you could post a pic of that.
