Funcionando M-Audio Audiophile 2496 (ICE1712) con Ubuntu Karmic Koala

A pesar de que las tarjetas M-Audio son muy utilizadas entre la comunidad de aficionados a la música, en todas las plataformas, ocurre que en Linux están teniendo un muy bajo soporte desde la inclusión de Pulse Audio.  Os adjunto la solución que ha funcionado para mí, y que debería funcionar para todas las tarjetas M-Audio con chip ICE1712, basada en la información que aparece referente al bug178442 de Launchpad:

Primero comprobamos el volumen de la tarjeta a través de envy24 control utility. Para ello instalamos el paquete que contiene dicho mixer:

$ sudo aptitude install alsa-tools-gui

Subimos los PCM al máximo y situamos todos los volumenes a 127 en la pestaña “Analog Volume”.

Tras esto cargamos los módulos de forma manual en lugar de automática, comentando las líneas #.ifexists #load-module #.else y #.endif y agregando dos líneas load-module en el fichero /etc/pulse/default.pa:

$ sudo vi /etc/pulse/default.pa

### Automatically load driver modules depending on the hardware available
#.ifexists module-udev-detect.so
#load-module module-udev-detect
#.else
### Alternatively use the static hardware detection module (for systems that
### lack udev support)
#load-module module-detect
#.endif
load-module module-alsa-sink sink_name=M2496_out device=hw:M2496 format=s32le channels=10 channel_map=left,right,aux0,aux1,aux2,aux3,aux4,aux5,aux6,aux7
load-module module-alsa-source source_name=M2496_in device=hw:M2496 format=s32le channels=12 channel_map=left,right,aux0,aux1,aux2,aux3,aux4,aux5,aux6,aux7,aux8,aux9

Es posible que con esto ya os funcione, pero todavía se puede hacer algo más:

Obtenemos nuestro subsystem_device (esto es para identificar el modelo de nuestra M-Audio, ya sea Terratec, Delta, Audiophile, etc:

$ sudo lspci -vvnnd1412:

05:01.0 Multimedia audio controller [0401]: VIA Technologies Inc. ICE1712 [Envy24] PCI Multi-Channel I/O Controller [1412:1712] (rev 02)
Subsystem: VIA Technologies Inc. Device [1412:d634]
Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- SERR-
Latency: 64
Interrupt: pin A routed to IRQ 22
Region 0: I/O ports at bc00 [size=32]
Region 1: I/O ports at b880 [size=16]
Region 2: I/O ports at b800 [size=16]
Region 3: I/O ports at b480 [size=64]
Capabilities:
Kernel driver in use: ICE1712
Kernel modules: snd-ice1712

En mi caso es la d634, así que:

1) agregamos la siguiente línea en /lib/udev/rules.d/90-pulseaudio.rules justo después de las dos líneas de SUBSYSTEMS:

$ sudo vi /lib/udev/rules.d/90-pulseaudio.rules

SUBSYSTEMS=="pci", ATTRS{vendor}=="0x1412", ATTRS{device}=="0x1712", ATTRS{subsystem_vendor}=="0x1412}, ATTRS{subsystem_device}=="0xd634", ENV{PULSE_PROFILE_SET}="via-ice1712.conf"

2) Creamos la definición para ice1712 incluyendo todo el texto que se adjunta en el fichero via-ice1712.conf:

$ sudo vi /usr/share/pulseaudio/alsa-mixer/profile-sets/via-ice1712.conf

#### Begin via-ice1712.conf ####
# This file is part of PulseAudio.
#
# PulseAudio is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as
# published by the Free Software Foundation; either version 2.1 of the
# License, or (at your option) any later version.
#
# PulseAudio is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with PulseAudio; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

; Via ICE1712 multi-channel audio chipset
;
; This chipset has up to four stereo pairs of input and four stereo pairs of
; output, named channels 1 to 8. Also available are separate S/PDIF stereo
; channels (input and output), and a separate “system-out” stereo jack that
; supports 6-channel hardware mixing.
;
; The S/PDIF stereo channels can be controlled via the mixer for hw:0, and
; additionally, the 8 main outputs can be loop-routed to a separate stereo
; input pair, available as channels 11 and 12.
;
; Many cards available from vendors do not expose all channels from this chip
; to an external port, which effectively reduces the number of channels that
; are useful to the user. However, the ALSA driver still exposes all channels
; even if they are not connected.
;
; We knowingly only define a subset of the theoretically possible
; mapping combinations as profiles here.
;
; See default.conf for an explanation on the directives used here.

[General]
auto-profiles = no

[Mapping analog-mch-in]
description = Analog Multi-Channel Main Input
device-strings = hw:%f,0
channel-map = front-left,front-right,rear-left,rear-right,front-center,lfe,side-left,side-right,aux0,aux1,aux2,aux3
direction = input

[Mapping analog-mch-out]
description = Analog Multi-Channel Main Output
device-strings = hw:%f,0
channel-map = front-left,front-right,rear-left,rear-right,front-center,lfe,side-left,side-right,aux0,aux1
direction = output

[Mapping digital-stereo]
description = Digital Stereo Input/Output
#device-strings = hw:%f,1
device-strings = iec958:%f
channel-map = left,right
direction = any

[Mapping analog-system-out]
description = Analog Stereo System-Out
device-strings = hw:%f,2
channel-map = left,right
direction = output

[Profile output:mch]
description = Multi-Channel Output Active (Digital Disabled)
output-mappings = analog-mch-out analog-system-out
input-mappings =
priority = 90
skip-probe = yes

[Profile output:mch+input:mch]
description = Multi-Channel Input/Output (Digital Disabled)
output-mappings = analog-mch-out analog-system-out
input-mappings = analog-mch-in
priority = 100
skip-probe = yes

[Profile output:spdif]
description = Digital Output (Multi-Channel Disabled)
output-mappings = digital-stereo analog-system-out
input-mappings =
priority = 80
skip-probe = yes

[Profile output:spdif+input:spdif]
description = Digital Input/Output (Multi-Channel Disabled)
output-mappings = digital-stereo analog-system-out
input-mappings = digital-stereo
priority = 90
skip-probe = yes

[Profile output:system]
description = System Output Only
output-mappings = analog-system-out
input-mappings =
priority = 60
skip-probe = yes
#### End via-ice1712.conf ####

Y aquí está mi Audiophile 2496 funcionando en Ubuntu Karmic Koala con PulseAudio: