I apologise if this has been answered hundreds of times before

I put all my music on internal storage, and my audio books on the sd card. of my e200.
Is there a way to tell rockbox when it creates a new play-list, to ignore anything on the sd card, without ejecting it first, otherwise, when I randomise my music, I get audio book tracks thrown in the mix as well.
Is there a better way to manage it?
Mr.G