Audio features
Adaptive audio
Adaptive audio is enabled by default. It supports the following Citrix Workspace app clients:
- Citrix Workspace app for Windows – 2109 and later versions
- Citrix Workspace app for Linux – 2109 and later versions
- Citrix Workspace app for Mac – 2109 and later versions
Adaptive audio falls back to legacy audio when you use a client not included on the list.
Adaptive audio dynamically adjusts audio sampling bitrates based on network conditions to enhance the audio experience, eliminating the need for manual configuration of audio quality policies on the VDA.
The following table shows a comparison between adaptive audio and legacy audio:
| Adaptive audio | Legacy audio |
|---|---|
| Max. audio sample rate: 48 kHz | Max. audio sample rate: 8 kHz |
| Stereo channel | Mono channel |
Audio service considerations
Starting with version 2407, the Linux VDA supports PipeWire in Debian 12.5, RHEL 9.x, and Rocky Linux 9.x, where it is the default audio service. For the other distributions, continue using PulseAudio.
PulseAudio
- Use PulseAudio 13.99 or later on RHEL 8.x and Rocky Linux 8.x.
PipeWire
The Linux VDA supports PipeWire only in Debian 12.5, RHEL 9.x, and Rocky Linux 9.x. Here are some considerations to take:
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If you have the Linux VDA version 2407 or later installed on Debian 12.5, RHEL 9.x, or Rocky Linux 9.x, you are using PipeWire.
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If you have a version of the Linux VDA earlier than 2407 installed on RHEL 9.x or Rocky Linux 9.x, you are using PulseAudio. To continue using PulseAudio, do nothing. To switch to PipeWire, complete the following steps:
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Replace the PulseAudio package with pipewire-pulseaudio:
dnf swap --allowerasing pulseaudio pipewire-pulseaudio <!--NeedCopy--> -
Enable PipeWire-related services globally:
systemctl --global --now enable pipewire pipewire-pulse pipewire-pulse.socket wireplumber <!--NeedCopy--> -
Restart the Linux VDA.
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Loss tolerant mode for audio (preview)
The loss tolerant mode supports audio. This feature increases the user experience for real-time streaming and improves audio quality over EDT when users are connecting through networks with high latency and packet loss.
For more information about the loss tolerant mode and EDT, see Additional information in the Citrix Virtual Apps and Desktops documentation.
Enable the loss tolerant mode for audio feature
Loss tolerant mode for audio is disabled by default. To enable it, complete the following steps:
- Enable adaptive transport by setting the HDX adaptive transport policy. Adaptive transport is enabled by default.
- Enable adaptive audio by setting the Adaptive audio policy. adaptive audio is enabled by default.
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Enable the loss tolerant mode (EDT unreliable transport) through the following registry setting:
ctxreg create -k "HKLM\System\CurrentControlSet\Control\Citrix\VirtualChannels\Audio" -t "REG_DWORD" -v "fEdtUnreliableAllowed" -d "0x00000001" --force <!--NeedCopy-->
Client requirements and settings
To use loss tolerant mode for audio, ensure that your Citrix Workspace app supports and is configured to enable this feature; otherwise, audio defaults to EDT Reliable transport.
The following are the minimum Citrix Workspace app versions that support loss tolerant mode:
- Citrix Workspace app for Windows minimum version 2309
- Citrix Workspace app for Linux minimum version 2311
- Citrix Workspace app for Mac minimum version 2311
Packet Loss Concealment for improving audio performance (preview)
Starting with the 2407 release, the jitter buffer mechanism is improved, and the Packet Loss Concealment (PLC) is added for the Adaptive audio codec. PLC helps to reconstruct the lost data packets. This enhancement helps to improve the packet loss tolerance and jitter tolerance and thus improves audio performance for loss tolerant mode (EDT lossy) for audio.
This feature is disabled by default. To enable this feature, complete the following steps:
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Enable the audio redirection feature that allows multiple audio device support.
sudo /opt/Citrix/VDA/bin/ctxreg create -k "HKLM\System\CurrentControlSet\Control\Citrix\VirtualChannels\Audio" -t "REG_DWORD" -v "fEnableAudioRedirectionV4" -d "0x00000001" --force <!--NeedCopy--> -
To enhance audio performance in loss tolerant mode, enable Read/Write V2 for audio:
ctxreg create -k "HKLM\System\CurrentControlSet\Control\Citrix\VirtualChannels\Audio" -t "REG_DWORD" -v "fEnableReadWriteV2" -d "0x00000001" --force <!--NeedCopy-->
Support for multiple audio devices (preview)
Overview
Starting with Version 2311, the Linux VDA introduces an audio redirection feature. The feature allows multiple audio devices on the client machine where Citrix Workspace app is installed to be redirected to the remote Linux VDA session.
With the feature enabled:
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All local audio devices on the client machine are displayed in a session. Instead of CitrixAudioSink (audio output) or CitrixAudioSource (audio input), the audio devices appear with their respective device names. You can select an audio device in an app in a session or use the default audio device during a session which is also the default audio device of the client machine. If necessary, you can change the default audio device from the system settings of the client machine. After the default audio device of the client machine is updated, the new device appears as the default audio device in the session.
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Audio devices within sessions update dynamically when you plug in or remove one.
Configuration
To use the feature, enable it on the Linux VDA and choose a supported Citrix Workspace app.
Enable the feature on the Linux VDA
The audio redirection feature that allows multiple audio device support is disabled by default. To enable it, run the following command on the Linux VDA:
sudo /opt/Citrix/VDA/bin/ctxreg create -k "HKLM\\System\\CurrentControlSet\\Control\\Citrix\\VirtualChannels\\Audio" -v "fEnableAudioRedirectionV4" -t BIN -d "1"
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To disable or re-enable the feature, run the following commands, respectively:
sudo /opt/Citrix/VDA/bin/ctxreg update -k "HKLM\\System\\CurrentControlSet\\Control\\Citrix\\VirtualChannels\\Audio" -v "fEnableAudioRedirectionV4" -d "0"
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sudo /opt/Citrix/VDA/bin/ctxreg update -k "HKLM\\System\\CurrentControlSet\\Control\\Citrix\\VirtualChannels\\Audio" -v "fEnableAudioRedirectionV4" -d "1"
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Client requirements and settings
The feature is supported only for the following clients:
- Citrix Workspace app for Windows
- Citrix Workspace app for Linux minimum version 2212
- Citrix Workspace app for HTML5 minimum version 2306
- Citrix Workspace app for Chrome minimum version 2306
- Citrix Workspace app for Mac minimum version 2311
Proper settings are required on Citrix Workspace app to make the feature function as expected. For more information, see the Citrix Workspace app documentation.
Known issues
Due to the issue with PulseAudio, attempts to switch between audio devices might fail in a Ubuntu 22.04 session. To address the issue, remove the PulseAudio configuration for the current session user from the VDA and then reopen the session. To remove the PulseAudio configuration, run the $ rm -r ~/.config/pulse command.