AWS Connect and static Citrix VDIs: Has anyone worked on this type of solution? We're using a Custom CCP, but even when we use AWS' default CCP, we're having issues: Missed Calls, One-way Audio, poor Call Quality. We've verified that HDX is redirecting Audio back to the end-point and that Call Traffic flows directly from the end-point to AWS on UDP 3478, but these issues persist. Is there anything on the Citrix side we might be missing? What about the end-points themselves?

Hi, we use it as scale successfully but I had to tackle a few issues 1. UDP 3478 - I had to get our FW allow it to various URLs, auto feed. 2. I had an issue with the offloading, I had it on the endpoint and on the Citrix worker. Make sure offloading is only happening on endpoint. 3. The miss calls and co makes think it's related to the control plane, probably the proxy blocking traffic. There are a few to allow. 4. Also check if your headsets are redirected correctly via Ctx policy. We use Chrome latest for it, W22 server, shared desktop.

Hi @jviteech, thanks for your Reply. What are you referring to when you say "Offloading"? We do have a few things "whitelisted" on the Proxy, do you know of some specific ones? I'll look into that CTX Policy...

offloading = when traffic flow from the endpoint. Endpoint is the device running CWA connecting to your desktop. I had some based on our custom domain, etc. I used the AWS guide providing the URLs. I worked with the security team to identify blocked traffic from the proxy.

OK that's what I thought. I've never heard of Offloading happening on the Citrix server... ? And I'm curious about your suggestion about Headsets... Doesn't the Citrix Policies "Client USB device redirection" and "Client USB Plug and Play device redirection" (both of which are Allowed for us) take care of this?

Offloading from server to the endpoint, not from, sorry. USB headset can sometimes be generic, not properly recognized.

So I just had an extended "conversation" with ChatGPT about this topic. Not only did it confirm what you noted about USB redirection, it also provided Citrix documentation and steps to configure HDX Optimization correctly AND a powershell script to check a list of VDIs for this. Pretty cool.

Great stuff! Let me know how you fix it.

So I just tried 2 of the recommended Registry settings on my own VDI: (1) configure Audio Quality for "Medium" (Optimized for Speech, and so that it will use UDP), and (2) Prohibit audio devices from doing "Client USB device redirection" ... Did a reboot of the VDI, and unfortunately it didn't work...

Hi @Greg Kern we use TCP for our gateway. Nothing is needed on CWA side to my knowledge. Which reg edit? the one needed to allow Chrome, Edge for offloading, the one provided by AWS? If it is, it's not overrided. Are your headset certified Teams? It could be a headset issue. We use Jabra, model HSC016 for example, Teams certified as WebRTC offloading was used by Teams v1.

Yeah this doesn't have anything to do with Teams... This is strictly about Amazon Connect and the Audio stream from the end-point to/from the VDI (via Citrix Gateways) and from the end-point to/from AWS Connect (UDP 3478). It's interesting that the Citrix documentation says to configure the "Audio Quality" Policy as "Medium - optimized for speech" instead of "High"...

I use medium also for the quality. It's probably more optimized for voice. It's not Teams BUT the offloading protocol used is the same than Teams v1, WebRTC on UDP 3478. So if Teams work fine, then AWS connect does. And headset is the same story. Does the quality improve if you use a home broadband connection? (No FW, etc.) What endpoint, CWA version do you use?

Hi @jvitech, sorry for the delayed Reply. So these Contractors are in Manila, and their support organization is responsible for their Internet connection. I think their Bandwidth is adequate but I should look into that a bit, probably... They're using CWA 2503, and we've made sure all appropriate Firewall rules, Azure NSGs, and Proxies are all configured to allow the traffic...

Hi, this doesn't look right. It looks like a generic device audio. Check my print screen, it's from Director, session details, Scroll down in the HDX session, you select audio and you get the details. HDX provides all the Citrix channels, audio, usb, graphics, etc. so you use it.

@jvitech, I'd like to continue this conversation if you don't mind? So I am uploading an Image file from a recent VDI session in which I tried to capture Device settings relative to HDX Audio Redirection. Would love to know your thoughts on it.

Download the Citrix Audio Diagnostics from https://citrix.com/downloads/citrix-citrix-tools Below capture from my session, shared desktop, same for all. I hope it helps.

That's almost exactly what I'm seeing on our end... We have "Audio over UDP" working, too...

Your devices are not coming under the proper name like me, they come under the generic Citrix. I wonder if the issue is related.

That's what's odd: I'm not sure we have an issue. I just want to make sure that Audio from the VDI session is being Redirected to the end-point, where the CWA media engine does all the processing before sending it out over UDP... Do you think that might be the case?

To be 100% sure it's offloaded, take a network capture, double check you see UDP 3478 from the endpoint and do the same on the VDA and confirm you don't. That's what I did. Let me know!

So a related question: As long as Citrix Policies are left at Default, HDX Audio will ALWAYS redirect to and process on the CWA, right? This came up in a conference call yesterday...

Hm only if you offload otherwise audio is going via the Citrix ICA audio channel (so processing happens on VDA) which is prob happening for you because your headset name. I may be wrong here but that doesn't sound right. Do the network capture to prove the point.

Not sure what you mean by "Offload"? Also, by "network capture" you're referring to WireShark, right? And I run that on my end-point or on the VDA? So if I start WireShark, then play an Audio file on my VDA, what would I expect to see in WireShark and/or on my end-point? Sorry for all the questions but Redirected Audio is a huge issue for our Off-Shore Call Center agents and we need to know exactly what's happening, so thank you!

Offload is when it's the endpoint processing the audio / video directly. Yes I refer to Wireshark, run it from the endpoint, if the offloading work, you should see the UDP traffic flowing. Also double check after there is no UDP from VDA, we had this issue at the beginning. Don't play a file audio, it won't be offloaded. Do the test when you use Amazon connect when on-call with someone else, a proper test. Do this test but I really think the issue occurs because your headset is not correctly redirected/not using the correct drivers, showing as Citrix HDX audio. And because of that offloading is not happening. So 1. confirm is offloading works or not with Wireshark. 2. If not aim to get the headset correctly showing up in Citrix. And see if it then works. Last did you try to disable the Citrix channel security as a test? It could prevent the offloading to work. https://docs.citrix.com/en-us/citrix-virtual-apps-desktops/2203-ltsr/secure/virtual-channel-security.html

Maybe I don't understand HDX Redirection: Doesn't it redirect ANY Audio from the VDA down to the end-point, and processes it there?