I cannnot get both of my outputs to work on my u-mix44

I cannot get both of my outputs to work when using mixvibes DVS software. I have tried switching the numbers to 1 and 2 but sound will only come out of which ever deck is selected to number 1. when I try this on mixvibes Cross I can get both outputs to work but when I try this in DVS only 1 output seems to work.I have also updated everything but I still am having the same problem. Could someone please help me
thank you
thank you