[mercy]

When we file nuts its done my hand and sight I understand. It would seem reasonable that there would be some variability in the final product. How many thousandths difference from ideal doesnt matter. Im seeing that in the action at the nut on my guitar.
The reason Im asking is that Im getting a rattle on my D and G strings. The action at the 12th is good at 6/64ths for both of them. When checking the action at the nut the action of each string is different. I would have thought that they should be the same at the nut. I understand why there would be more action at the 12th to give room for string wobble but thats not an issue at the nut.
Is there some way for a tech to get the same action at the nut? Is that improtant? Do I need to have a new nut filed to get rid of the D/A rattle?