Color issues exist such as bleeding and over/under saturation etc.
The issue is possibly caused by filters being incorrectly applied during transcoding (i.e. saturation filter, color space conversion filter etc). Ensure that no unnecessary filters were set during transcoding of the source.
Another possibility is that at some point the content has been derived from a composite video source which resulted in bleeding or dot crawl. There are filters available that attempt to correct this, however the best course of action is to seek an alternate source.
Newer material should be free from these issues and it should be an easy process to find a better source. Older material may prove more challenging. Should it not be possible to locate a better source for older material please contact your Netflix representative via Backlot.