3CX on RDS voice quality (static, dropouts, robot voice)

[Lucian Burns]

First time caller. We have rolled out two Azure RDS hosts for our COVID inspired work from home remote access solution, staff are at home using a mix of devices, work owned and otherwise. Inside the same Azure tenancy is our 3CX server. We have are experiencing various degrees of very poor voice call quality. Here are our observations, in all instances this is the 3CX Windows application installed:

1. 3CX from within RDS session, calling mobile phone network - quality is fine
2. 3CX from within RDS session, internal call, call answered on 3CX from within another RDS session - quality is awful (like really bad)
3. 3CX from local computer, calling mobile phone network - quality is fine
4. 3CX from local computer, internal call, call answered on 3CX from another local computer - awful again

No combination of port, codec, tunnel or non-tunnel, other configurations on the 3CX client application, seem to make any difference.

Sype, Slack, Teans, etc. all run beautifully for any of these locations (in fact better than 3CX quality has ever been).

Further info, our preference is to use 3CX inside the RDS session as otherwise agents cant see call queues, in some cases calls dont pop over the top of the RDS session, etc. I know some are using 3CX on the local computer Ok, would be very curious to know how that was made successul in a call centre environment.

I guess I have two questions.

Q1. Does anyone have any pointers to where I should go to troubleshoot further?
Q2. Does anyone know of alternate call software I can integrate with 3CX to handle the 'last mile' communications.

Regarding Q2 I am thinking that if I could leave 3CX doing the queue and agent work, but divert all the phones at the server side to some non-3CX agent for the voice work then perhaps I can side-step around this issue until we can get it fixed e.g. stupid example (cause almost certainly not possible), 3CX extension diverted to Skype, you know something like that but replace Skype with XXX (?)

Any other advice greatly appreciated, this is killing us at the moment and we cannot properly service our customers. Many thanks in advance.

 

[Lucian Burns]

PS. please move me to correct thread if mis-posted, my apologies if so.

 

[diamond9]

Hi @Lucian Burns

We are running very similar setup, we are currently getting little problems here and there but i am currently putting it down to local internet on the agents computers with call quality, not sure if you have tried testing the PBX delivers audio option being on and off, i would be interested to see where we get with all this, could be helpfull for future installs as this is the way we are all going remote desktop/TS environments.

My current customer is using the windows app with USB headsets on their local computers, we host the RDS and 3CX in our own datacentre rack.

I would rather try getting the solution to work with 3cx fully rather than diverting off to other applications as thats could get messy in some environments and you will then be using 2 sim calls for 1 incoming call

 

[Lucian Burns]

Hi @diamond9 , many thanks for your kind response. I will chat to our engineers now about the "PBX delivers audio option", do some more tests, and post up results.

It is indeed hard with so many factors involved but I have been careful and methodical to investigate local internet performance (using speedtest.net), RDS connection bandwidth (using NetLimiter), latency (using Performance Monitor on RDS host), etc. and I cannot find any fault at the local computer environment for the ones I am using in my testing.

Ill get those test results shortly...

 

[Lucian Burns]

3CX support came back and suggested we adjust the codecs (we sent them detailed logs collected with fiddler). We had both PCMU and G.729. They said try just a single codec, and try PCMA. We tried all options and no difference i.e. PCMU, G.729, PCMA, all the same bad voice quality when calling 3CX-RDS to 3CX-RDS.

We also tried @diamond9 suggestion of "PBX delivers audio". Our system had it switched on, so we switched it off to test. Voice quality was same i.e. terrible when calling 3CX-RDS to 3CX-RDS.

 

[diamond9]

Just another thing to try and ive just thought this might be helpful for us to try, have you got a local DNS entry for your PBX FQDN pointing to the internal IP of the 3cx so if you ping the FQDN from the RDS does it resolve the local ip?

 

[Lucian Burns]

From command prompt on RDS host, ping working to FQDN.

 

[diamond9]

No problem, but quickly remove that screen shot, you dont want your FQDN out there for people to attempt

 

[Lucian Burns]

They could probably guess it but agreed no point poking the bear!!

 

[diamond9]

Are you using Linux or windows for your 3cx server?

 

[Lucian Burns]

Linux. We increased the Azure VM to 4 cores and 16GB mem.

 

[CentrexJ]

Use local soft phone, set to pop to foreground, also get USB headsets that have software that works with 3CX for answer button on the Cord. We use plantronics headsets with plantronics hub.

 

[Lucian Burns]

Thanks @CentrexJ, I havent investigated the detail myself, and pop to foreground worked for me, but I have a BA who was testing this saying it didnt pop to the front, assume you have never seen that? Also I wonder how you handle queues etc. again I am not across the detail but call centre staff say they need to be able to see the queue. [edit] ps. we have two screens but both used for applications.

 

[CentrexJ]

So from the rds side of things they can run the 3CX web client which will show the queue as well as it can also control the soft phone client on the local pc. You select the soft phone at the top right of web client.

 

[Lucian Burns]

Thanks @CentrexJ that promises to be an incredibly effective solution, and seems very simple. We will try this and share outcomes.

 

[Lucian Burns]

Initial results are very promising, I was able to call from within RDS host to another user within RDS host with no quality issues (accepting that the actual call was conducted from local computers but just orchestrated from within RDS host). The web client worked nicely and problems. The one thing I did was disabled pop to front on the 3CX application on local computer, to avoid user confusion. Continuing testing and will share outcomes.

 

[Lucian Burns]

I also note that somewhere I read that the 3cx web client you can use the google "Save as App" feature (https://support.google.com/chrome_webstore/answer/3060053?hl=en) to make it work more like an application in its own separate window, couldnt get it to work initially on our RDS but perhaps due to restrictions in place, not sure. Something I will follow up on.

 

[Lucian Burns]

Update, this is working well in proof of concept with exception of following:
1. Web Client doesn't have a method to place on hold
2. Sometimes declining a call in web client doesn't terminate the call

@CentrexJ are these issues you have seen in your own environments, do you have any solutions. Many thanks in advance.

 

[CentrexJ]

1 if it’s short use the mute button on the USB headset cable
2 only on queue or ring groups with ring all option but that is for any scenario

 

[diamond9]

Call queues you cannot decline the call it will represent, ring group you should be able to.