Confbridge sound quality

Hi I am having some sound quality issues with Asterisk V10.12.2-1 and confbridge calls.

A sip trunk is built from and Avaya Communication Manager and the Asterisk box. I have restricted the codec down to G.711A 20ms

Both systems are on the same subnet and the TOS value is set and matches the switches.

The audio is however cutting out and sounds as if there is some packet loss. I get this issue in my lab as well but had always thought it was related to my ESXI server running multiple servers at the same time.

Does anyone have a guide to improving voice quality or know of any common mistakes which relate to sound quality issues of this type?

Any assistance is greatly received

Anyone have issues with Webmin on an asterisk server?

Ah! Although I have changed the default port on webmin to something other than 10000 it looks like it uses port 10000 udp for some auto discovery feature which is conflicting asterisks default rtp setting in rtp.conf

I still have a few audio quality issues even with the webmin service stopped.

The investigation continues

It’s very likely that running it in your virtualized environment is contributing to the problem. Virtualized environments do not provide extremely reliable timing from which to derive audio mixing. It can be somewhat reliable, in that it works okay, but it’s inferior to running on bare metal.

That said, you can turn on the receive-side jitterbuffer and play around with the mixing interval.

I have upgraded my lab to include a reasonable spec dedicated asterisk server but I’m still getting issues.

The first sign of audio issues is when after the first announcement on a call which you can hear a “Tshhhhhhh” sound which dissipates to nothing in approximately 2 seconds.

The second is choppy prompts. This occurs when I see high processor utilization for a short period of time. This is a quad core xeon with 4GB of ram and a gig Ethernet interface on a switch with just my laptop and a Cisco sip handset so probably not related to QOS or overloaded with calls.

The third is related to the second when I load the system up with 4 calls I can sometimes get a repeating of part of the last prompt. For example i have put a macro together which simply counts. after a period of time I may start to here "One hundred and fifty five… five) for 155. If I put the call on hold and resume sometimes this will correct the issue.

Anyone have any symptoms like this?

Has anyone else seen thease type of audio replay issues?
“Tshhhhhhh” sound after system annoucments
Choppy prompts.
Repeating of part of the last prompt. For example i have put a macro together which simply counts. after a period of time I may start to here "One hundred and fifty five… five) for 155. If I put the call on hold and resume sometimes this will correct the issue.

I rearly could do with some help to fix this.

I’m keen to try some ideas before opening a bug with digium.

Thanks

I managed to get rid of most of my sound quality issues by prioritising applications below asterisk and by throwing more processor at my systems but I still get a Tshhhhhhh at the end of and announcement. Is there a setting to cut off audio and not send a Tshhhhhh?