Here's the deal.
I use grey cards all the time, so there is always a reference for starters, and I have no color issues whatsoever...until I use the ND filters. Also, I agree about the presets. They suck.
I also agree that the Kodak cards are lame as well, but I have had no problem getting correct color using it...until I use the ND filters. I am currently getting a set of proper grey cards, but I have used them in the past and they did nothing for this current situation.
The other photographer I talked to that has the same problem is using Tiffen filters, and I am using Lee, and the filters are new. There is a chance it could be the back.
I'm using ND filters because I am on an automotive rig shoot, meaning I need 4-8 second exposures in the middle of the day. I understand that ND's are not as common now, but they are still very important in the market I work in.
Here is a good example of the problem.
We used an ND Grad on one shot to get more detail in the sky. Used a grey card, color balanced the shot, and the sky was light red. It was light red because it was the only part of the shot where the ND filter was applied. Everything else was neutral. No grey card can fix that problem! If I tried to make the sky look proper, the rest of the shot was screwed up.
If anyone has a chance, try getting a hold of an ND or ND Grad filter and see what happens.