Tex, My claim of validity is the number of posts I've replied to that have a problem connected to a combo unit. I have no proof as such. I'm sure what you state is true, only some combo units (and likely some routers as well) present connection problems. Perhaps all of the problems these folks have are configuration based. In this particular case the GenieGO apparently doesn't list the combo unit that the OP is using in the set-up menu. Not sure what else to offer.
mightyo, Texasbrit was addressing me and had a query as to my post regarding a router. An exchange between those of us responding to your problem occurs on occasion as we try to come up with the best advice to provide you.