Recordbox and XDJ-R1 output problems, I need an experts help !!

Hi im using Recordbox with the XDJ-R1, when I select PC input on both Decks on the R1, Recordbox will not allow me to play music through both decks (with two players selcted) it will play music through the left deck with Output 1+2 selected, but then to play through the other deck I have to de-select 1+2 and select output 3+4, its seems to automatically black out 2 channels at any one time, is there any way of selecting all four outputs? So i can use the fader on the deck. Im using XLR outputs to a pair of active speakers.