The best way to handle this would be to make sure you have the pre build task disabled. NCrunch usually disables these by default, but if you've implemented it with a custom target then you may need to add a condition to it:

<Target Name="BeforeBuild" Condition="$(NCrunch) != '1'">
....
</Target>

Generally speaking, it isn't good practice to have absolute file references within your solution as this can cause NCrunch to exhibit the recursive behaviour you've described. Another way to fix this would be to replace the absolute AssemblyInfo.cs reference with a relative path instead.