$ cat /proc/asound/cards
 0 [Intel          ]: HDA-Intel - HDA Intel
                      HDA Intel at 0xd0540000 irq 16

$ cat /proc/asound/devices
  0: [ 0]   : control
  1:        : sequencer
 16: [ 0- 0]: digital audio playback
 18: [ 0- 2]: digital audio playback
 24: [ 0- 0]: digital audio capture
 25: [ 0- 1]: digital audio capture


$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC880 Analog [ALC880 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 2: ALC880 Digital [ALC880 Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0



$ amixer info
Card default 'Intel'/'HDA Intel at 0xd0540000 irq 16'
  Mixer name    : 'Realtek ALC880'
  Components    : 'HDA:10ec0880'
  Controls      : 36
  Simple ctrls  : 20


$ mplayer -ao alsa:device=spdif -ac hwac3 disneydvd.vob 
---snip---
Forced audio codec: hwac3
Opening audio decoder: [hwac3] AC3/DTS pass-through S/PDIF
No accelerated IMDCT transform found
hwac3: switched to AC3, 448000 bps, 48000 Hz
AUDIO: 48000 Hz, 2 ch, ac3, 448.0 kbit/29.17% (ratio: 56000->192000)
Selected audio codec: [hwac3] afm: hwac3 (AC3 through S/PDIF)
==========================================================================
[AO_ALSA] alsa-lib: pcm_hw.c:1248:(snd_pcm_hw_open) open /dev/snd/pcmC0D1p failed: No such file or directory
[AO_ALSA] alsa-lib: pcm_hw.c:1248:(snd_pcm_hw_open) open /dev/snd/pcmC0D1p failed: No such file or directory
[AO_ALSA] Playback open error: No such file or directory
Could not open/initialize audio device -> no sound.



$ mplayer -ao alsa:device=hw=0.2 -ac hwac3 disneydvd.vob
----snip----
forced audio codec: hwac3
Opening audio decoder: [hwac3] AC3/DTS pass-through S/PDIF
No accelerated IMDCT transform found
hwac3: switched to AC3, 448000 bps, 48000 Hz
AUDIO: 48000 Hz, 2 ch, ac3, 448.0 kbit/29.17% (ratio: 56000->192000)
Selected audio codec: [hwac3] afm: hwac3 (AC3 through S/PDIF)
==========================================================================
[AO_ALSA] alsa-lib: conf.c:3830:(parse_args) Unknown parameter AES0
[AO_ALSA] alsa-lib: conf.c:3952:(snd_config_expand) Parse arguments error: No such file or directory
[AO_ALSA] alsa-lib: pcm.c:2143:(snd_pcm_open_noupdate) Unknown PCM hw:0,2,AES0=6
AO: [alsa] 48000Hz 2ch ac3 (1 bytes per sample)
Starting playback...