This describes the following configuration:

SUSE Linux 10.0 on i686 and x86_64,
Sound hardware: Multimedia audio controller: Creative Labs SB Audigy (rev 04)

"aplay -L" lists the following multi-speaker PCM's:

cards 'cards.pcm'
front 'cards.pcm.front'
rear 'cards.pcm.rear'
center_lfe 'cards.pcm.center_lfe'
side 'cards.pcm.side'
surround40 'cards.pcm.surround40'
surround41 'cards.pcm.surround41'
surround50 'cards.pcm.surround50'
surround51 'cards.pcm.surround51'
surround71 'cards.pcm.surround71'
iec958 'cards.pcm.iec958'
spdif 'cards.pcm.iec958'
modem 'cards.pcm.modem'
default 'cards.pcm.default'
dmix 'cards.pcm.dmix'
dsnoop 'cards.pcm.dsnoop'

Running "aplay -D {center_lfe,front,rear} some_wavfile.wav" plays the sound on the speakers of my 5.1 speaker system (Teufel Concept E Magnum) as expected. Using the surround PCM as in "aplay -D surround51 some_wavfile.wav" results in the following error message:

aplay: set_params:897: Channels count non available

This used to work in former versions (SLES 9 & SL-9.2); while this is not too bad for wavfiles, it is annoying when trying to play DVDs encoded with 5.1 surround sound either in DolbyDigital 5.1 or in DTS. The result is some endlessly stuttering sound (both in xine and mplayer from packman); choosing "Stereo 2.0" makes xine to play sound, but it's obviously only two channel sound without the luxury of the remaining 4 channels... Also, the sound is quite distorted from time to time - suddenly the clear sound breaks up and gets distorted, while after some time it suddenly becomes clear again.

Please tell me if you need any further details.

Here's the output from running "hwinfo --sound":
18: PCI 0e.0: 0401 Multimedia audio controller                  
  [Created at pci.277]
  UDI: /org/freedesktop/Hal/devices/pci_1102_4
  Unique ID: vuMS.9jPiZAnlR97
  SysFS ID: /devices/pci0000:00/0000:00:0e.0
  SysFS BusID: 0000:00:0e.0
  Hardware Class: sound
  Model: "Creative SB Audigy 2 ZS (SB0350)"
  Vendor: pci 0x1102 "Creative Labs"
  Device: pci 0x0004 "SB Audigy"
  SubVendor: pci 0x1102 "Creative Labs"
  SubDevice: pci 0x2002 "SB Audigy 2 ZS (SB0350)"
  Revision: 0x04
  Driver: "EMU10K1_Audigy"
  I/O Ports: 0xb000-0xb03f (rw)
  IRQ: 201 (42499 events)
  Module Alias: "pci:v00001102d00000004sv00001102sd00002002bc04sc01i00"
  Driver Info #0:
    Driver Status: snd_emu10k1 is active
    Driver Activation Cmd: "modprobe snd_emu10k1"
  Driver Info #1:
    Driver Status: emu10k1 is not active
    Driver Activation Cmd: "modprobe emu10k1"
  Config Status: cfg=yes, avail=yes, need=no, active=unknown