Assembly parts rotate 90 degree

Hello

In an assembly I am having problems with how a sub assembly acts in the full assembly.

It is a fully defined sub assembly but yet it will rotate 90degrees out of postiion until I rebuild then

will rebuild correctly until I do something else in the assembly. for instance add another part to it, or, just rotate the assembly

to check, then it will rotate 90 degrees again.

thankyou

Mark

IDFI

SolidworksAssemblies