asound.conf

# ~/.asoundrc or /etc/asound.conf
# ALSA configuration file

##### USAGE #####
# Save this file as "~/.asoundrc" (for user-specific sound configuration) or
# "/etc/asound.conf" (for system-wide sound configuration) and specify ALSA
# device names ad described in the next section.


##### DEVICE NAMES #####
# This configuration file defines four devices for use by the user.  Those
# devices are "analog", "mixed-analog", "digital", and "mixed-digital".  The
# user may also re-define "default" to be identical to one of the above-named
# devices (i.e. to send all sound output to the digital output unless otherwise
# specified).  Use the device names as described below:
#  - "analog" outputs to the analog output directly and (at least on software
#  sound cards) blocks other audio output.  After playback completes, "queued"
#  sounds are output in sequence.
#  - "mixed-analog" mixes audio output from multiple programs into the analog
#  output (so you can hear beeps, alerts, and other noises while playing back
#  an audio stream).
#  - "digital" outputs to the digital output directly.  Since most (all?)
#  digital outputs expect 48kHz PCM audio, this may not work for some playback
#  (i.e. CD's--which are 44.1kHz PCM audio--or 32kHz audio streams from TV
#  recordings, etc.).
#  - "mixed-digital"

# All other devices created within this file are used only by the configuration
# file itself and should /not/ be used directly.  In other words, do not use
# the devices "analog-hw", "dmix-analog", "digital-hw", or "dmix-digital".


##### IMPORTANT #####
# To make this ALSA configuration file work with your sound card, you will need
# to define the appropriate card and device information for the "analog-hw" and
# "digital-hw" devices below.  You can find the card and device information
# using "aplay -l".

# Alias for (converted) analog output on the card
# - This is identical to the device named "default"--which always exists and
# refers to hw:0,0 (unless overridden)
# - Therefore, we can specify "hw:0,0", "default", or "analog" to access analog
# output on the card
# - Note that as of ALSA 1.0.9, "software" sound card definitions redefine
# "default" to do mixing, meaning this device is different from "default" and
# allows playback while blocking other sound sources (until playback
# completes).
pcm.analog {
    type plug
        slave.pcm "analog-hw"
        hint {
            show on
                description "Analog Output - Use analog outputs, converting samples, format, and rate as necessary."
        }
}

# Control device (mixer, etc.) for the card
ctl.analog {
    type hw
        card 0
}

# Alias for (converted) mixed analog output on the card
# - This will accept audio input--regardless of rate--and convert to the rate
# required for the dmix plugin (in this case 48000Hz)
# - Note that as of ALSA 1.0.9, "software" sound card definitions redefine
# "default" to do mixing, meaning this device is identical to "default" for
# "software" sound cards.
pcm.mixed-analog {
    type plug
        slave.pcm "dmix-analog"
        hint {
            show on
                description "Mixed Analog Output - Use analog outputs, converting samples, format, and rate as necessary. Allows mixing with system sounds."
        }
}

# Control device (mixer, etc.) for the card
ctl.mixed-analog {
    type hw
        card 0
}

# Alias for (converted) digital (HDMI) output on the card
pcm.digital {
    type plug
        slave.pcm "digital-hw"
        hint {
            show on
                description "Digital Output - Use digital outputs, converting samples, format, and rate as necessary."
        }
}

# Control device (mixer, etc.) for the card
ctl.digital {
    type hw
        card 0
}

# Alias for mixed (converted) digital (HDMI) output on the card

pcm.mixed-digital {
    type plug
        slave.pcm "dmix-digital"
        hint {
            show on
                description "Mixed Digital Output - Use digital outputs, converting samples, format, and rate as necessary. Allows mixing with system sounds."
        }
}

# Control device (mixer, etc.) for the card
ctl.mixed-digital {
    type hw
        card 0
}

# The following devices are not useful by themselves.  They require specific
# rates, channels, and formats.  Therefore, you probably do not want to use
# them directly.  Instead use of of the devices defined above.

# Alias for analog output on the card
# Do not use this directly--it requires specific rate, channels, and format
pcm.analog-hw {
    type hw
        card 0
        device 0
}

# Control device (mixer, etc.) for the card
ctl.analog-hw {
    type hw
        card 0
}

# Alias for digital (HDMI) output on the card
# Do not use this directly--it requires specific rate, channels, and format
pcm.digital-hw {
    type hw
        card 0
        device 1
}

# Control device (mixer, etc.) for the card
ctl.digital-hw {
    type hw
        card 0
}

# Direct software mixing plugin for analog output on the card
# Do not use this directly--it requires specific rate, channels, and format
pcm.dmix-analog {
    type dmix
        ipc_key 1234
        slave {
            pcm "analog-hw"
                period_time 0
                period_size 1024
                buffer_size 4096
                rate 48000
        }
}

# Control device (mixer, etc.) for the card
ctl.dmix-analog {
    type hw
        card 0
}

# Direct software mixing plugin for digital (S/PDIF) output on the card
# Do not use this directly--it requires specific rate, channels, and format
pcm.dmix-digital {
    type dmix
        ipc_key 1235
        slave {
            pcm "digital-hw"
                period_time 0
                period_size 1024
                buffer_size 4096
                rate 48000
        }
}

# Control device (mixer, etc.) for the card
ctl.dmix-digital {
    type hw
        card 0
}

# Make joint analog/HDMI the default
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
}

# Control device (mixer, etc.) for the card
ctl.!default {
    type hw
        card 0
}

pcm.xbmc {
    type plug
        slave {
            pcm multi
                rate 48000
                channels 4
        }
    ttable.0.0 1.0
        ttable.1.1 1.0
        ttable.0.2 1.0
        ttable.1.3 1.0
}


ctl.xbmc {
    type hw
        card 0
}

pcm.multi {
    type multi
        slaves.a.pcm "analog-hw"
        slaves.a.channels 2
        slaves.b.pcm "digital-hw"
        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
}

I have got two beaglebone black revc.
I would like make the usb audio device C-Media default
When I typed cat /etc/asound.conf, I get a message "cat: /etc/asound.conf: No such file or directory"
Then I try to check whether I have asound.conf. I have found you file link to upload asound.conf which I colud noy achieve
Can you help me to create such file in order to modify it ?
I believe I need to make the USB audio device system wide I need to modify the file asound.conf as 💯
pcm.!default {
type hw
card 1
#device 0
}
ctl.!default {
type hw
card 1
#device 0
}
Pls help me to resolve the problem

@mttumay
cd /etc // go to that folder where you need asound.conf file.
sudo touch asound.conf // this will create a file name asound.conf.
sudo nano asound.conf // write what you want and press CTRL + O to save the file.

I know it's too late to replay. Anyway.