Answer

If the mix is exported from ProTools in "Film" order, encoded as DTS or Dolby, and then burned onto a file, the DCIO will see the channel tags within the bitstream and re-arrange. Note that this does not apply to the NV Series, since those devices cannot decode bitstream.

If using a source like ProTools or VLC and you are sending PCM out with untagged channels, the NV Series devices and the DCIO will see those at face value - i.e., channel one will go to channel one. In this case, there is no way for the DCIO to know what channel is which because the output doesn't have the channel ID metadata.

If a device like a Blu-ray player is doing the decoding for you and it is decoding DTS or Dolby, there is a possibility that the DCIO will arrange the channels in film spec instead of SMTPE and flip your channels. However, if the device decodes in SMTPE format, then the channels should arrive to the NV and DCIO in the correct order. Again, this only applies when dealing with PCM or decoding from other third party devices.