How To: Output Sound from S/PDIF And Analog Jacks Simultaneously

sultanoswing · 2010-07-19 03:31:55

A common problem and annoyance is the inability to easily output sound simultaneously from the S/PDIF digital and analog jacks on most on-board solutions. In this case my motherboard is an ASUS P7P55D-E-Pro using the VIA VT1828S on-board audio chip.

In Windows XP, sound is delivered out both jacks, but this was redesigned in Vista and 7.

A workaround in Vista/7 is to set the audio output to analog, then set individual applications to output to digital (or vice versa).

In linux the following ~/.asoundrc file was successful in at last outputting to both digital and analog simultaneously, so I can once again send music to my home theater amp in another room via S/PDIF at the same time as I'm typing and listening on the PC, which is connected via the analog jacks.

pcm.!default {
type plug
slave {
pcm multi
rate 48000
}
ttable.0.0 1.0
ttable.1.1 1.0
ttable.0.2 1.0
ttable.1.3 1.0
}
pcm.stereo {
type plug
slave {
pcm multi
rate 48000
}
ttable.0.0 1.0
ttable.1.1 1.0
ttable.0.2 1.0
ttable.1.3 1.0
}
ctl.stereo {
type hw
card 0
}
pcm.multi {
type multi
slaves.a.pcm "hw:0,0"
slaves.a.channels 2
slaves.b.pcm "hw:0,1"
slaves.b.channels 2
bindings.0.slave a
bindings.0.channel 0
bindings.1.slave a
bindings.1.channel 1
bindings.2.slave b
bindings.2.channel 0
bindings.3.slave b
bindings.3.channel 1
}
ctl.multi {
type hw
card 0
}

NOTE: In the above "hw:0,0" and "hw:0,1" are found by entering 'aplay -l' in a terminal, which lists card #, device #. If you only have one on board sound card, then no need to change to above code.

Also ensure sure the both S/PDIF switches are 'on' in alsamixer. I have this working perfectly in amarok (phonon-gstreamer backend, with 'default' audio selected) under Gnome 2.30.2 / Arch Linux x86_64.

FWIW, my /etc/asound.conf file reads:

pcm.!default {
type plug
slave {
pcm "hw:0,1"
# pcm "spdif"
rate 48000
}
}

ctl.!default {
type hw
card 0
}

Hope this is helpful! For me, I can at last retire my SoundBlaster Audigy 2ZS, which does the above by default

Last edited by sultanoswing (2010-07-19 04:06:38)

Arch Linux

#1 2010-07-19 03:31:55

How To: Output Sound from S/PDIF And Analog Jacks Simultaneously

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