столкнулся с такой проблемой: при включении пункта vmix0-enable[vmix0-rate:48.000kHz] с параметром vmix0-channels=multich (т.к система у меня 5.1) в ossxmix звук ужасно искажается(как перегрузка идет), зато работают сабвуфер и фронтальная колонка. При отключении данного пункта или смене vmix0-channels на stereo звук снова нормальный, зато сабвуфер и фронт отключаются. В чем может быть проблема? прилагаю скриншот, если непонятно изложил

"vmix0-enable" означает включить Виртуальный Миксер.
Если вы его выключаете, тогда ресемплирование (SRC) будет делать сама "soundcard".
В обычных встроенных картах внутренний ресемлер низкокачественный.
А в крутых фирмовых картах, внутренний ресемплер работает отлично.
Если у вас обычная карта, интегрированная в motherboard, тогда имеет смысл включить vmix, а также, задействовать "Production quality".Читайте всю тему с самого начала.
http://wiki.archlinux.org/index.php/Allow_multiple_programs_to_play_sound_at_once#vmix_-_OSS.27_Software_Mixing_System.
vmix - OSS' Software Mixing System.
OSS (Open Sound System) is an open-source sound architecture (alternative to ALSA) that contains a software mixer (vmix) in kernel-space. The vmix software mixer comes enabled by default in OSS, and works out-of-the-box. See OSS for more information.
http://www.4front-tech.com/forum/viewtopic.php?f=3&t=3755#p14849vmix is a layer in OSS with several roles: software mixing (like dmix in ALSA), SRC conversion, and binding between output and input (for duplex and convenience purposes. Note that output and input don't have to be same device). It needs to be bound to a device node to work. Most drivers do this automatically, but some drivers for high end device do not (like lynxtwo). In these cases (or when the default is bad for some reason), the "vmixctl" utility can be used to attach vmix. See "vmixctl" manpage (via "man vmixctl" command), and here...
Using vmix will create fake software "engines" (i.e. outputs) under the specified output device (you can see them in 'ossinfo -v2' output) which can be used for mixing purposes (each outputting program occupies an output engine), but they're possibly of inferior quality to the soundcard's hw mixing. In any event, it is certain you want to avoid the SRC conversion (usually decent, but unnecessary here, so can only lead to quality loss). To be sure no SRC is done, either set "vmix0-src" to OFF in the mixer (via ossmix or ossxmix)...
on Terminal:
ossinfo
EXAMPLE:
$ ossinfo
Version info: OSS 4.2 (b 2002/201003260436) (0x00040100) GPL
Platform: Linux/i686 2.6.32-ARCH #1 SMP PREEMPT Mon Mar 15 20:08:25 UTC 2010 (cargo-cult)
Number of audio devices: 7
Number of audio engines: 11
Number of MIDI devices: 0
Number of mixer devices: 1
Device objects
0: osscore0 OSS core services
1: oss_hdaudio0 Intel HD Audio interrupts=232632 (232632)
HD Audio controller Intel HD Audio
Vendor ID 0x80862668
Subvendor ID 0x17c02017
Codec 0: AD1986A (0x11d41986/0x17c02017)
Codec 1: Motorola3055 (0x10573055)
2: oss_usb0 USB audio core services
MIDI devices (/dev/midi*)
Mixer devices
0: High Definition Audio AD1986A (Mixer 0 of device object 1)
Audio devices
HD Audio play front /dev/oss/oss_hdaudio0/pcm0 (device index 0)
HD Audio play rear /dev/oss/oss_hdaudio0/pcm1 (device index 1)
HD Audio play center/LFE /dev/oss/oss_hdaudio0/pcm2 (device index 2)
HD Audio play spdif-out /dev/oss/oss_hdaudio0/spdout0 (device index 3)
HD Audio play modem /dev/oss/oss_hdaudio0/mdmout0 (device index 4)
HD Audio rec rec-srcmic-mix /dev/oss/oss_hdaudio0/pcmin0 (device index 5)
HD Audio rec modem /dev/oss/oss_hdaudio0/mdmin0 (device index 6)
Nodes
/dev/dsp -> /dev/oss/oss_hdaudio0/pcm0
/dev/dsp_in -> /dev/oss/oss_hdaudio0/pcm0
/dev/dsp_out -> /dev/oss/oss_hdaudio0/pcm0
/dev/dsp_ac3 -> /dev/oss/oss_hdaudio0/spdout0
/dev/dsp_mmap -> /dev/oss/oss_hdaudio0/pcm0
/dev/dsp_multich -> /dev/oss/oss_hdaudio0/pcm0
Вопросы по "surround sound" лучше задавать на OSS4
http://www.4front-tech.com/forum/viewforum.php?f=3