Have you tried rotating btwn a couple/few different kibbles? That can sometimes help as it keeps them enticed / stimulated with the different flavors/smells.   
Have you tried Natures Logic yet? That's a very nice kibble.     
				__________________  ~ A friend told me I was delusional. I nearly fell off my unicorn.  ~    °¨¨¨°ºOº°¨¨¨° Ann | Pfeiffer | Marcel Verdel Purcell | Wylie | Artie  °¨¨¨°ºOº°¨¨¨°      |