Please follow the instructions you found in the alsa docs.
So, after loading the module "snd-rme32" you should have an entry
in /proc/asound/cards:
0 [Digi32 ]: Digi32 - RME Digi32
RME Digi32 (Rev. 192) at 0xd8000000, irq 9
The status of the card can be checked with "cat
/proc/asound/card0/rme32" which depends on your card-number.
Finally it would produce some output in this style:
RME Digi32 (Rev. 192) at 0xd8000000, irq 9 (index #1)
General settings
receiver: CS8412
format: 16 bit, Stereo
Input settings
input: optical
sample rate: no valid signal
Output settings
output signal: normal playback (muted)
sample rate: 44100 Hz
sample clock source: Internal
format: IEC958 (consumer)
emphasis: off
Change of that values is possible with mixers like amixer. This
card has no typical volume control like other cards, so it's
possible to have a mixer which won't work. Another way is to use a
graphical frontend like rmedigicontrol for this job.
