AI traffic with VoxATC X

HiI just bought VoxATC X and look forward to spend the weekend in 'ATC land'. However, one thing that buggers me is that while my addon AI traffic (My Traffic X) works fine around the airports, only the FSX stock airplanes show up while enroute. This is a bit annoying as the stock planes are not near as frame rate friendly as the My Traffic ones and they also lack the diversity of the many liveries included in the AI package.Does anybody know why this is so and how it can be remedied?/ Thanks in advance, Poul