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https://github.com/luisbocanegra/linux-guide-split-audio-ports

Split jack(headphones)/speakers outputs into individual sinks on Linux to allow simultaneous playback (listen to different audio streams on each port)
https://github.com/luisbocanegra/linux-guide-split-audio-ports

alsa audio laptop linux pipewire sound

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Split jack(headphones)/speakers outputs into individual sinks on Linux to allow simultaneous playback (listen to different audio streams on each port)

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README 

        
# Splitting audio ports in Linux for simultaneous playback



![Plasma audio volume widget showing split ports](pics/linux-full-multistreaming-plasma-panel.png)



## Introduction



On windows some laptops have the option to enable the playback of different audio streams on different audio outputs, for example you could listen to a video call in the browser through your wired headphones, while playing music from Spotify on the internal speakers.



Such option can have a different name depending on the sound card or laptop's vendor, for my laptop, an **HP Omen 15-dc100xxx with a ALC295 card** it is called _multistreaming_ and can be enabled from the **OMEN Audio Control** program.



Here's some screenshot showcasing that feature on Windows:



![multistreaming option in windows OMEN Audio Control](pics/hp-omen-multistreaming-feature.png)



And this is how you route programs' audio to an individual output:



![volume mixer in windows](pics/windows-volume-mixer.png)



On Linux I don't have such an option, so can only listen one output at a time



That is:



- You have to unplug your wired speakers/headphones to be able to play anything from the internal speakers,

- And if you connect a wired speakers/headphones:

  - The internal speaker is muted, hidden from the gui and marked as unavailable



    ![speakers unavailable in linux](pics/speakers-unavailable.png)



  - Audio streams are switched to your wired output without giving you the desired output option like windows does



    ![applications without output option in pavucontrol](pics/linux-audio-mixer.png)



## The final result



If you follow until [part 2](https://github.com/luisbocanegra/linux-guide-split-audio-ports#3-splitting-for-simultaneous-playback-with-alsa-firmware-patch-for-different-applications-on-each-port)



- Allow selecting and playing audio from the internal speakers while a wired output is connected



If you follow till the end



- Have a separate audio sink for each output

- Play different audio streams on each card port, simultaneously (e.g. Spotify on speakers and Firefox on Headphones)



![pavucontrol with multistreaming enabled](pics/linux-full-multistreaming.png) **Note:** The program used in above screenshots is `pavucontrol`



## Requirements



- PipeWire

- alsa-card-profiles

- alsa-utils

- alsa-tools

- pavucontrol



## 1 Preparations, analyze how the card appears on Linux



### 1.1 Gather some information about the card



Run `pactl list cards` and save the output somewhere, bellow is a stripped

 version of mine to keep the important things



```yaml

Card #46

    Name: alsa_card.pci-0000_00_1f.3

    Driver: alsa

    Properties:

            api.alsa.path = "hw:0"

            device.product.id = "0xa348"

            device.vendor.id = "0x8086"

    ...

    Profiles:

            output:analog-stereo+input:analog-stereo: Analog Stereo Duplex (sinks: 1, sources: 1, priority: 6565, available: yes)

            output:analog-stereo: Analog Stereo Output (sinks: 1, sources: 0, priority: 6500, available: yes)

            input:analog-stereo: Analog Stereo Input (sinks: 0, sources: 1, priority: 65, available: yes)

            pro-audio: Pro Audio (sinks: 4, sources: 1, priority: 1, available: yes)

    Active Profile: output:analog-stereo+input:analog-stereo

    Ports:

            analog-output-speaker: Speakers (type: Speaker, priority: 10000, latency offset: 0 usec, availability group: Legacy 3, availability unknown)

                    Properties:

                            port.type = "speaker"

                            port.availability-group = "Legacy 3"

                            device.icon_name = "audio-speakers"

                            card.profile.port = "2"

                    Part of profile(s): output:analog-stereo, output:analog-stereo+input:analog-stereo

            analog-output-headphones: Headphones (type: Headphones, priority: 9900, latency offset: 0 usec, availability group: Legacy 4, availability unknown)

                    Properties:

                            port.type = "headphones"

                            port.availability-group = "Legacy 4"

                            device.icon_name = "audio-headphones"

                            card.profile.port = "3"

                    Part of profile(s): output:analog-stereo, output:analog-stereo+input:analog-stereo

```



Card details:



```yaml

Name: alsa_card.pci-0000_00_1f.3

Ports: analog-output-speaker analog-output-headphones

Profiles: output:analog-stereo input:analog-stereo output:analog-stereo+input:analog-stereo

device.product.id = "0xa348"

device.vendor.id = "0x8086"

```



As we can see, this laptop has three audio profiles, one for all audio outputs 

and other for all inputs, with an extra one that has both inputs and outputs (yours may vary)



### 1.2 Inspect the audio sinks available for our sound card



Run `pactl list sinks` and save the output, bellow is a stripped

version of mine to keep the important things



```yaml

Sink #47

    State: RUNNING

    Name: alsa_output.pci-0000_00_1f.3.analog-stereo

    Description: Built-in Audio Analog Stereo

    Driver: PipeWire

    ...

    Ports:

            analog-output-speaker: Speakers (type: Speaker, priority: 10000, availability group: Legacy 3, not available)

            analog-output-headphones: Headphones (type: Headphones, priority: 9900, availability group: Legacy 4, available)

    Active Port: analog-output-headphones

    Formats:

            pcm

```



Sink details:



```yaml

Name: alsa_output.pci-0000_00_1f.3.analog-stereo

Ports: analog-output-speaker analog-output-headphones

Active Port: analog-output-headphones

```



As we can see, there is only one audio sink that can play audio on the two outputs individually (yours may vary)



## 2 disable Headphone jack detection for speakers



**Note:** `alsa-card-profile` files are provided by `alsa-card-profiles` package



1. First copy the contents of folder `/usr/share/alsa-card-profile/mixer/paths/` to `/etc/alsa-card-profile/mixer/paths/`



    ```sh

    mkdir -p /etc/alsa-card-profile/mixer/

    sudo cp -r /usr/share/alsa-card-profile/mixer/paths/ /etc/alsa-card-profile/mixer/

    ```



2. Next we need to modify the mixer path in `/etc/alsa-card-profile/mixer/paths/` that matches the speakers port, in my case is `analog-output-speaker`.



    It is **crucial** to pick the correct one, to verify you did, change `description-key` value to something else (e.g. by removing the last letter) and restart pipewire (`systemctl restart --user pipewire pipewire-pulse pipewire.socket wireplumber`) the mixer path file name will show in pavucontrol or `pactl list sinks` instead of the actual port name:



    ```yaml

    Ports:

        analog-output-speaker: analog-output-speaker (type: Unknown, priority: 10000, availability group: Legacy 4, available)

    ```



3. Delete all the other files in `/etc/alsa-card-profile/mixer/paths/` leaving only your mixer path and the common file e.g:



    ```sh

    sudo find /etc/alsa-card-profile/mixer/paths/ -type f ! -name 'analog-output-speaker.conf' ! -name 'analog-output.conf.common' -exec rm -f {} +

    ```



4. Change the `description-key` back to the default, then:



   - Set `state.plugged = unknown` inside the **Jack** section that best matches the wired port name of your card, in my case is `analog-output-headphones` so I use `[Jack Headphone]` one:



       ```ini

       [Jack Headphone]

       state.plugged = unknown

       state.unplugged = unknown

       ```



   - Comment (by adding semi-colon on start of line) the **Element** section that matches the port `[Jack ...]` in my case is `[Element Headphone]`:



       ```ini

       ; [Element Headphone]

       ; switch = off

       ; volume = off

       ```



5. Save the changes and restart the audio server by running:



    ```sh

    systemctl restart --user pipewire pipewire-pulse pipewire.socket wireplumber

    ```



    If everything went well you should have the speaker option available without having to unplug your wired device and



   - Should be able to play audio on them (individually)

   - Audio streams should still change automatically from speakers to your wired output and vice versa when plugging/unplugging a wired device



    ![pavucontrol with speakers available](pics/linux-audio-mixer-speakers-available.png)



Congratulations! We're closer to our final goal, but you may stop here if this was your desired behavior 🙂



## 3 Splitting for simultaneous playback with alsa firmware patch (for different applications on each port)



### 3.1 Analyze the card sub devices



First we need to identify and check if our card has more than one sub device and test if sound comes out of them



Run



```sh

aplay -l

```



You'll get something like the following



```ini

**** List of PLAYBACK Hardware Devices ****

card 0: PCH [HDA Intel PCH], device 0: ALC295 Analog [ALC295 Analog]

  Subdevices: 1/1

  Subdevice #0: subdevice #0

...

```



At this point, my card `card 0` (ALC295), has only one sub device, you may have more, take note of this information as we'll need it later



We can confirm the playback (output) and capture (input) streams the card currently has with `cat /proc/asound/pcm`



```yaml

00-00: ALC295 Analog : ALC295 Analog : playback 1 : capture 1

...

```



### 3.2 Making the alsa firmware patch file



#### Option 1 Using hdajackretask



1. Run `hdajackretask`

2. In the Select a codec drop-down select your card

3. In the Options section check `Parser hints`

4. In the Hints list set `indep_hp` and `` to yes with double click on them.

5. Press `Install boot override`

6. Open the file `/lib/firmware/hda-jack-retask.fw` and add `vmaster=no` below `indep_hp=yes`

7. **Reboot to apply the changes**



#### Option 2 Manually (non-immutable distributions)



Run



```sh

cat /proc/asound/card*/codec#* | grep -E 'Codec|Vendor Id|Subsystem Id|Address'

```



You'll get the codecs in the following format, pick the one that matches your card (mine is the `Realtek ALC295`):



```yaml

Codec: Realtek ALC295

Address: 0

Vendor Id: 0x10ec0295

Subsystem Id: 0x103c8575

...

```



With the above we can start creating our patch file:



1. Create the file (don't copy as is, modify according to explanation bellow):



    `/lib/firmware/hda-jack-retask.fw`



    ```ini

    [codec]

    0x10ec0295 0x103c8575 0



    [hints]

    indep_hp=yes

    vmaster=no

    ```



    Below `[codec]` line we should put the values of `Vendor Id`, the `Subsystem Id` and `Address` of the card, separated by spaces.



    Below `[hints]` we need to add what is called hint strings



   - `indep_hp=yes` this will make for our jack output to be detected as an independent PCM stream with its own controls (meaning it will split away from internal speakers as a separate audio sink for us to play specific app stream on it).



   - `vmaster=no` will disable the virtual Master control so we can control volume on each port individually.



2. Create the following file:



    `/etc/modprobe.d/alsa-base.conf`



    ```sh

    options snd-hda-intel patch=hda-jack-retask.fw

    ```



3. **Reboot to apply the changes**



#### Option 3 Manually for immutable distributions using script and udev rule



For immutable distros `/lib/firmware/` is not writable. As a workaround you can use an udev rule that sets the hints on boot. **This method may cause some noises during boot and is not warranted to be as reliable as the firmware one, if that's the case, suggestions to improve it are welcome**



1. Create the file `/etc/udev/rules.d/91-pipewire-alsa-port-split.rules` (don't copy as is, modify according to explanation bellow)



    ```sh

    SUBSYSTEM!="sound", GOTO="pipewire_end"

    ACTION!="change", GOTO="pipewire_end"

    KERNEL!="card*", GOTO="pipewire_end"



    SUBSYSTEMS=="pci", ATTRS{vendor}=="0x8086", ATTRS{device}=="0xa348", \

    RUN+="/usr/local/bin/alsa-split-ports.sh"



    LABEL="pipewire_end"

    ```



2. Create the script `/usr/local/bin/alsa-split-ports-hints.sh` and set `CODEC` `VENDOR_ID` and `SUBSYSTEN_ID` with the ones from your card from `cat /proc/asound/card*/codec#* | grep -E 'Codec|Vendor Id|Subsystem Id|Address'`, note how the `CODEC` variable doesn't have the vendor name (`Realtek`) because whe are matching against `/sys/class/sound/hw*/chip_name`



   ```sh

    #!/usr/bin/env bash

    CODEC="ALC295"

    VENDOR_ID="0x10ec0295"

    SUBSYSTEN_ID="0x103c8575"

    HINTS="indep_hp = yes

    vmaster = no

    "



    get_codec_hwdep() {

        local codec=$1

        local vendor_id=$2

        local subsystem_id=$3

        local addr=""

        [[ -z "$codec" || -z "$vendor_id" || -z "$subsystem_id" ]] && { echo "ERROR: Not enough arguments given"; return; }

        for file in /sys/class/sound/hw*; do

            if [[ -n "$addr" ]]; then

            echo "$addr"

            return

            fi

            if grep -q "$codec" "$file/chip_name" && grep -q "$vendor_id" "$file/vendor_id" && grep -q "$subsystem_id" "$file/subsystem_id"; then

                addr=$file

            fi

        done

        if [[ -z "$addr" ]]; then

        echo "ERROR: Could not get address for c:$codec v:$vendor_id s:$subsystem_id"

        return

        fi

    }

    # get_codec_hwdep "$CODEC" "$VENDOR_ID" "$SUBSYSTEN_ID"

    hwdep="$(get_codec_hwdep "$CODEC" "$VENDOR_ID" "$SUBSYSTEN_ID")"



    if [[ "$hwdep" == *"ERROR"* || -z "$hwdep" ]]; then

    exit 1

    fi



    while IFS=$'\n' read -r line; do

    if [[ -z "$line" ]]; then

        continue

    fi

    echo "$line > ${hwdep}/hints"

    echo "$line" > "${hwdep}"/hints

    done <<< "$HINTS"



    echo "echo 1 > ${hwdep}/reconfig"

    echo 1 > "${hwdep}"/reconfig



    # wait some time to intialize before restoring

    sleep 5

    alsactl restore

   ```



3. **Reboot to apply the changes**



### 3.3 Verify that the patch works



Run again



```sh

aplay -l

```



You _should_ get something like the following



```ini

**** List of PLAYBACK Hardware Devices ****

card 0: PCH [HDA Intel PCH], device 0: ALC295 Analog [ALC295 Analog]

  Subdevices: 0/1

  Subdevice #0: subdevice #0

card 0: PCH [HDA Intel PCH], device 2: ALC295 Alt Analog [ALC295 Alt Analog]

  Subdevices: 1/1

  Subdevice #0: subdevice #0

```



Now the card ALC295 (`card 0`), has an extra sub device (`2`), interesting...



Run `cat /proc/asound/pcm`, if there is a new sub device and has a playback sub-stream (`playback 1`) like below you can continue



```yaml

00-00: ALC295 Analog : ALC295 Analog : playback 1 : capture 1

00-02: ALC295 Alt Analog : ALC295 Alt Analog : playback 1

...

```



#### 3.3.1 Identify what output each device corresponds to



1. Plug-in your wired audio device then run `alsamixer -c0` (replace 0 with your card #number if needed)

   1. Un-mute any muted device (the ones with MM below the volume slider) pressing `m`

   2. Increase their volume to around 30 if the're on 0

   3. Enable `Independent HP` if is not enabled

   4. Press `Esc` to exit.



   ![alsamixer with unmuted outputs](pics/alsamixer-unmuted-outputs.png)



2. Finally, save it by running



    ```sh

    sudo alsactl store

    ```



3. Stop any running pipewire services (may need to stop it multiple times if it gets restarted):



    ```sh

    systemctl --user stop pipewire.service pipewire.socket pipewire-pulse.service pipewire-pulse.socket wireplumber.service

    ```



4. Run `speaker-test -Dhw:0,0 -c2` (replace 0,0 with the card #number and device #numbers from your card from `aplay -l`)



    For the device 0 (speaker-test -Dhw:0,0 -c2) the sound comes out from the speakers, so `device 0` is the speakers



5. Repeat for all the devices for your card and note which device corresponds to which physical output



So my card's outputs are the following (yours may vary):



- Device `0,0` (card 0, device 0) handles Speakers (and also microphones, as we saw in `cat /proc/asound/pcm`)

- Device `0,2` (card 0, device 2) handles Headphones



## 4 Making a custom alsa profile for our card



### 4.1 Now is time to do a recap of all information we have captured



Card details:



```yaml

Name: alsa_card.pci-0000_00_1f.3

Ports: analog-output-speaker analog-output-headphones

Profiles: output:analog-stereo input:analog-stereo output:analog-stereo+input:analog-stereo

```



Sink details:



```yaml

Name: alsa_output.pci-0000_00_1f.3.analog-stereo

Ports: analog-output-speaker analog-output-headphones

Active Port: analog-output-headphones

```



Card sub devices and playback (outputs) / capture (inputs) location:



```ini

**** List of PLAYBACK Hardware Devices ****

card 0: PCH [HDA Intel PCH], device 0: ALC295 Analog [ALC295 Analog]

  Subdevices: 0/1

  Subdevice #0: subdevice #0

card 0: PCH [HDA Intel PCH], device 2: ALC295 Alt Analog [ALC295 Alt Analog]

  Subdevices: 1/1

  Subdevice #0: subdevice #0

```



```yaml

00-00: ALC295 Analog : ALC295 Analog : playback 1 : capture 1

00-02: ALC295 Alt Analog : ALC295 Alt Analog : playback 1

...

```



So in my case I have:



- Two ports: `analog-output-speaker analog-output-headphones`

- Device locations for the card 0 correspond to:

  - Device `0,0` (card 0, device 0) Speakers (also handles microphones)

  - Device `0,2` (card 0, device 2) Headphones



### 4.2 Create the profile



1. Rename your mixer path file from [2 disable Headphone jack detection for speakers](#2-disable-headphone-jack-detection-for-speakers) like below:



    ```sh

    sudo mv /etc/alsa-card-profile/mixer/paths/analog-output-speaker.conf /etc/alsa-card-profile/mixer/paths/analog-output-speaker-split.conf

    ```



2. Now create the file `/etc/alsa-card-profile/mixer/profile-sets/split-ports-profile.conf`



    ```sh

    sudo mkdir /etc/alsa-card-profile/mixer/profile-sets/

    sudo touch /etc/alsa-card-profile/mixer/profile-sets/split-ports-profile.conf

    ```



3. Open split-ports-profile.conf with your preferred editor, paste the following and adapt it to your system according to the comments:



    ```ini

    ; This will let alsa generate automatic profiles (e.g internal speaker + microphone)

    [General]

    auto-profiles = yes



    ; device-strings describes the ALSA device string(s) that PulseAudio uses to open the device, where "%f" specifies the card number (should always be present in the string).



    ; This is the mapping for the internal speaker

    ; If needed, change the 0 in "hw:%f,0" to your sub device location

    ; You can change the description for this and other mappings if you want

    ; in paths output put the name of the previously created custom mixer path

    [Mapping analog-stereo-speaker]

    description = Speakers

    device-strings = hw:%f,0

    paths-output = analog-output-speaker-split

    channel-map = left,right

    direction = output



    ; This is the mapping for the jack output (headphones)

    ; If needed, change the 2 in "hw:%f,2" to your sub device location

    ; in paths output put the name of the from card details

    [Mapping analog-stereo-headphones]

    description = Headphones

    device-strings = hw:%f,2

    paths-output = analog-output-headphones

    channel-map = left,right

    direction = output



    ; This is the mapping that will handle internal and external microphones, as you could see in `cat /proc/asound/pcm`, the card also had a capture port

    ; in the 0,0 sub device location so let's add it here too (change the 0 in "hw:%f,0" to your sub device location that has the capture port)

    ; All the paths-input names here came from the default.conf profile set and you may have to adapt it if your input port name is not included



    [Mapping analog-stereo-input]

    description = Microphone

    device-strings = hw:%f,0

    channel-map = left,right

    paths-input = analog-input-front-mic analog-input-rear-mic analog-input-internal-mic analog-input-dock-mic analog-input analog-input-mic analog-input-linein analog-input-aux analog-input-video analog-input-tvtuner analog-input-fm analog-input-mic-line analog-input-headphone-mic analog-input-headset-mic

    direction = input



    ; Broken in parts the profile name means to join

    ; The name of the Mapping containing the analog-output-headphones (output:analog-stereo-headphones)

    ; The name of the Mapping containing the analog-output-speaker (output:analog-stereo-speaker)

    ; The name of the Mapping containing the analog-stereo-input (input:analog-stereo-input)



    ; in output-mappings put the name of the output mappings

    ; input-mappings put the name of the input mappings



    ; NOTE: Not to be confused width the paths-output/paths-input inside the mapping, we're not using those directly



    ; This is the profile that will have the internal speakers + jack output + all microphones

    ; in paths output put the name of the from card details

    [Profile output:analog-stereo-headphones+output:analog-stereo-speaker+input:analog-stereo-input]

    description = Analog Stereo Duplex

    output-mappings = analog-stereo-headphones analog-stereo-speaker

    input-mappings = analog-stereo-input

    priority = 80



    ; This profile will have the internal speakers + jack output, but not microphones

    [Profile output:analog-stereo-headphones+output:analog-stereo-speaker]

    description = Analog Stereo Outputs Only

    output-mappings = analog-stereo-headphones analog-stereo-speaker

    priority = 70

    ```



### 4.3 Link the profile to the card



1. Create the file `/etc/udev/rules.d/91-pipewire-alsa-port-split.rules` (don't copy as is, modify according to explanation bellow). Also, if using the udev rule to apply hints from [Using script and udev rule for immutable distros](#using-script-and-udev-rule-for-immutable-distros) you can use the commented rule instead.



    ```sh

    SUBSYSTEM!="sound", GOTO="pipewire_end"

    ACTION!="change", GOTO="pipewire_end"

    KERNEL!="card*", GOTO="pipewire_end"



    SUBSYSTEMS=="pci", ATTRS{vendor}=="0x8086", ATTRS{device}=="0xa348", \

    ENV{ACP_PROFILE_SET}="/etc/alsa-card-profile/mixer/profile-sets/split-ports-profile.conf"



    # Use this instead for immutable distributions

    # SUBSYSTEMS=="pci", ATTRS{vendor}=="0x8086", ATTRS{device}=="0xa348", \

    # ENV{ACP_PROFILE_SET}="/etc/alsa-card-profile/mixer/profile-sets/split-ports-profile.conf" \

    # RUN+="/usr/local/bin/alsa-split-ports.sh"



    LABEL="pipewire_end"

    ```



2. Replace the vendor and device id with `device.vendor.id` and `device.product.id` respectively, that you got in [1.1 Gather some information about the card](#11-gather-some-information-about-the-card)



3. **Reboot to apply the changes**



### 5 Verify the split worked



Open pavucontrol and in the **Configuration** tab select the `Analog Stereo Duplex` profile for your card



![image](https://github.com/luisbocanegra/linux-guide-split-audio-ports/assets/15076387/f6d57989-4e03-4f17-a28d-a5421577dbb2)



Run



```sh

pactl list sinks | grep -E 'Name|Desc|State|Port|device.profile-set'

```



I everything went well you should have a separate audio sink for each output:



```yaml

State: IDLE

Name: alsa_output.pci-0000_00_1f.3.analog-stereo-headphones

Description: Built-in Audio Headphones

        device.profile-set = "/etc/alsa-card-profile/mixer/profile-sets/split-ports-profile.conf"

Ports:

Active Port: analog-output-headphones

State: SUSPENDED

Name: alsa_output.pci-0000_00_1f.3.analog-stereo-speaker.2

Description: Built-in Audio Speakers

        device.profile-set = "/etc/alsa-card-profile/mixer/profile-sets/split-ports-profile.conf"

Ports:

Active Port: analog-output-speaker-split

```



Now you should be able to play different applications on each sink, you can do that with pavucontrol or KDE's Audio Volume widget. Congratulations! 🎉



## Stuck or didn't work? Found an mistake or something isn't clear enough?



If you faced any problems or are stuck [please open a new issue](https://github.com/luisbocanegra/linux-guide-split-audio-ports/issues/new) including the information [as described here](https://github.com/luisbocanegra/linux-guide-split-audio-ports/issues/9)



## Support me



This guide is the result of days of effort hunting for the right information and lots of reading. If it was useful to you consider making a small donation



[!["Buy Me A Coffee"](https://img.shields.io/badge/Buy%20me%20a%20coffe-supporter?logo=buymeacoffee&logoColor=%23282828&labelColor=%23FF803F&color=%23FF803F)](https://www.buymeacoffee.com/luisbocanegra)



## Credits & Resources



- Docs

  - [Linux Kernel Sound Subsystem Documentation](https://www.kernel.org/doc/html/v6.7/sound/)

    - [More Notes on HD-Audio Driver](https://www.kernel.org/doc/html/v6.7/sound/hd-audio/notes.html)

    - [Proc Files of ALSA Drivers](https://www.kernel.org/doc/html/v6.7/sound/designs/procfile.html)

  - [ALSA Documentation](https://www.alsa-project.org/wiki/Documentation)

- [How to output unique audio to multiple ports/profiles of a PulseAudio card?](https://unix.stackexchange.com/questions/401492/how-to-output-unique-audio-to-multiple-ports-profiles-of-a-pulseaudio-card)