How do I assign headphone channels for auditioning in Multigrids with a PreSonus Firestudio mobile? Route Outputs only offers the choices of DAW 1, DAW2, DAW3,...DAW6; no channels labeled headphone (I assume DAW5/6 are those outputs). The various permutations of output routings isn't making it possible for headphone to do anything other than mirror outputs 1&2 or 3&4. Perhaps this is a PreSonus issue?