Steve, I converted a couple of the clips to mono but still get the same results. I deleted the buses and afterwards the panning and volume work as they should at the track level.
 
Then I created a new bus but get the same results as before. So I must be doing something wrong somewhere when I create the bus. Will tinker around some more. Thanks for your reply and suggestions.

Well, I tried another plugin (reverb) instead of Guitar Rig 5 and it works as it should. So it looks like Guitar Rig 5 is the problem. Don't really know why at this point? Will tinker around some more. I am in stereo with GR5. Anyone else have any problems with GR5? Thanks.