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  • Group Policy Default Settings for Citrix Virtual Apps and Desktops That Changed Between 2106 and 2109

    Computer Multi-session Settings:

    • Changed: Multi-Stream virtual channel stream assignment – Removed “App Flow: 2”
    • Added: VDA data collection for Performance Analytics – Prohibited
    • Changed: Virtual channel allow list – Enabled: Blank

    Computer Single-session Settings:

    • Changed: Multi-Stream virtual channel stream assignment – Removed “App Flow: 2”
    • Changed: Virtual channel allow list – Enabled: Blank

    User Multi-session Settings:

    • Added: Adaptive audio: Allowed
    • Changed: Drag and drop: Disabled

    User Single-session Settings:

    • Added: Adaptive audio: Allowed
    • Changed: Drag and drop: Disabled



    About Carl Webster

    Carl Webster is an independent consultant specializing in Citrix, Active Directory, and technical documentation. Carl (aka “Webster”) serves the broader Citrix community by writing articles (see and by being the most active person in the Citrix Zone on Experts Exchange. Webster has a long history in the IT industry beginning with mainframes in 1977, PCs and application development in 1986, and network engineering in 2001. He has worked with Citrix products since 1990 with the premiere of their first product – the MULTIUSER OS/2.

    View all posts by Carl Webster

    6 Responses to “Group Policy Default Settings for Citrix Virtual Apps and Desktops That Changed Between 2106 and 2109”

    1. Geir Sandstad Says:

      Hi Carl.
      That would be nice… if the delivey controllers had been already updated. Unfortunately, that’s still a bit into the future.
      We would still like to use VDA version 2112 before that to benifit from the improved display performance, since we have a lot of users on VDI with vGPU acceleration. The problem is that if we start using the latest VDA version and a user happens to have a newer version of Citrix Workspace App, the audio will fail since we can’t disable Adaptive Audio. Part of the problem is also that we do not have configured firewall openings to allow for audio over UDP and/or RTP.
      We will get there eventually, but it can take a while…


      • Carl Webster Says:

        Adaptive audio uses the same transport offered by the legacy codec. There should be no firewall or network change needed.

        You can disable Adaptive audio using the following reg key:

        Windows Registry Editor Version 5.00

        Put the computers needing AA disabled into a security group and apply a GPO/GPP with that regkey to that security group.



        • Geir Sandstad Says:

          Thanks Carl, that was just what I was looking for.
          Just tested and verified that this works (not that I ever doubted it).

          Merry xmas to you, stay safe!


        • Geir Sandstad Says:

          Now… this is sort of embarrassing. I thought I’d do a bit more testing, just to see if I could find a different angle to solve the problem.
          To make sure I really was starting fresh I did a reboot of the VDI, logged back in… and adaptive audio works.
          I most have forgotten the basics earlier, always from scratch when you have an issue.

          I first saw this issue after upgrading CWA on my work computer. I must have only disconnected from the session during that upgrade, and not signed out completely. So when I connected again with my upgraded CWA, Adaptive Audio was connected but didn’t work.
          So something was set on the VDI from when I used the older version of CWA, and that didn’t reset when I reconnected with the new version. A fresh sign-in to a new VDI in the same pool fixed that issue. Nothing else was changed on the VDI-side. These are random pooled VDIs, so the new VDI I signed in to has been running all the time.

          That the audio came back when I added the registry key to disable Adaptive Audio also probably threw me off from the real issue. I only tested by adding the key, disconnect and reconnect again.

          That means, there could still be a very minor issue here, popping up when a user disconnects their session, upgrades CWA and connects again. Luckily, its easily fixed by signing out and signing back in to a fresh VDI.
          This might seem like a minor thing, but the users I support are used to just disconnecting from their VDIs and stay signed in for long periods. So, if a new version of CWA is deployed in the mean time, they might just disconnect for the update, reconnect and find that the audio does not work anymore.


    2. Geir Sandstad Says:

      Hi. Is there a way of disabling adaptive audio if the delivery controller has not yet been upgraded to 2109 or newer? If you are running VDA for example VDA 2109 and the latest version of Workspace app, it automatically selects Adaptive Audio. This doesn’t work for our environment, most likely due to network and firewall configurations. This will be looked in to, but in the mean time we would like the configuration to fall back to the same as before Adaptive Audio was introduced.


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