Not sure if this will help, but I had a similar problem with a CM8738 sound card with both coaxial and tos-link out. I already had a coax cable present so used that. The 1204 scripts that set up the sound card for this particular MD upon every reboot kept placing "plughw:0,1" in /etc/asound.conf. What I needed was asound.conf to read: "plughw:0,2". I didn't figure that out until trying
speaker-test -D plughw:0,2. Using aplay -L helped me identify that right device number.
To keep the correct "0,2" in place after a reboot, I had to edit /usr/pluto/template/asound.conf.