russel
./_dazed_and_confused
Next thing to do would simply be running the command 'aplay -L' which should list where it thinks the MDAC's IEC958 handle is, then somehow decoding that to the relevant ALSA output. When my onboard soundcard (yuck) was active, it would cause a re-order of device enumeration.
Here is the output from the command:
pulse
Playback/recording through the PulseAudio sound server
front:CARD=NVidia,DEV=0
HDA NVidia, VT1708S Analog
Front speakers
surround40:CARD=NVidia,DEV=0
HDA NVidia, VT1708S Analog
4.0 Surround output to Front and Rear speakers
surround41:CARD=NVidia,DEV=0
HDA NVidia, VT1708S Analog
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=NVidia,DEV=0
HDA NVidia, VT1708S Analog
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=NVidia,DEV=0
HDA NVidia, VT1708S Analog
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=NVidia,DEV=0
HDA NVidia, VT1708S Analog
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=NVidia,DEV=0
HDA NVidia, VT1708S Digital
IEC958 (S/PDIF) Digital Audio Output
hdmi:CARD=NVidia,DEV=0
HDA NVidia, NVIDIA HDMI
HDMI Audio Output
front:CARD=MDAC,DEV=0
Audiolab M-DAC, USB Audio
Front speakers
surround40:CARD=MDAC,DEV=0
Audiolab M-DAC, USB Audio
4.0 Surround output to Front and Rear speakers
surround41:CARD=MDAC,DEV=0
Audiolab M-DAC, USB Audio
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=MDAC,DEV=0
Audiolab M-DAC, USB Audio
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=MDAC,DEV=0
Audiolab M-DAC, USB Audio
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=MDAC,DEV=0
Audiolab M-DAC, USB Audio
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=MDAC,DEV=0
Audiolab M-DAC, USB Audio
IEC958 (S/PDIF) Digital Audio Output
I guess there is an Alsa module missing.