rohde@anette:~$ speaker-test -c6 -Dplug:surround51 -t wav -l1

speaker-test 1.0.14

Playback device is plug:surround51
Stream parameters are 48000Hz, S16_LE, 6 channels
WAV file(s)
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 8 to 10920
Period size range from 4 to 5460
Using max buffer size 10920
Periods = 4
was set period_size = 0
was set buffer_size = 10920
Unable to set sw params for playback: Invalid argument
Setting of swparams failed: Invalid argument



rohde@anette:~$ aplay -L
default:CARD=Revolution51
    M Audio Revolution-5.1, ICE1724
    Default Audio Device
front:CARD=Revolution51,DEV=0
    M Audio Revolution-5.1, ICE1724
    Front speakers
surround40:CARD=Revolution51,DEV=0
    M Audio Revolution-5.1, ICE1724
    4.0 Surround output to Front and Rear speakers
surround41:CARD=Revolution51,DEV=0
    M Audio Revolution-5.1, ICE1724
    4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=Revolution51,DEV=0
    M Audio Revolution-5.1, ICE1724
    5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=Revolution51,DEV=0
    M Audio Revolution-5.1, ICE1724
    5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=Revolution51,DEV=0
    M Audio Revolution-5.1, ICE1724
    7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=Revolution51,DEV=0
    M Audio Revolution-5.1, ICE1724
    IEC958 (S/PDIF) Digital Audio Output
null
    Discard all samples (playback) or generate zero samples (capture)