Voice Mail issues

[TLCtech]

3CX Version, e.g. Standard Annual 16.0.9
Server OS, Raspberry Pi 4
3cx hosted locally
Provisioning Method: Local
Trunk Provider: Call Centric
Has the Firewall Checker passed: YES
Are custom Phone Templates being used: NO

This is yet another audio issue we have been facing with our system. We will get a voice mail left that is garbled, the audio is all out of order, or there are large chunks of dead air between even letters in a word. We have no idea what is going on. And I've tried just about everything I can think of.

What causes this?

File is located here
https://sndup.net/3m4x

It's so garbled, I don't even have to edit it for privacy.

 

[VoIPTools]

My first guess is you are using SIP trunks and have insufficient internet bandwidth to handle the audio reliably (get a faster internet connection), or your Raspberry Pi is underpowered for what you are asking it to do.

 

[ChrisC_3CX]

As VOIPTools said, first thing I'd recommend is to check if this 3CX Instance is compliant with our hardware requirements. Check where it says ARM-Based.

If everything regarding resources is in order, to start troubleshooting the issue I'd first recommend trying to narrow it down a bit:

• How often does it happen? Can the issue be reproduced?
• Is it only for incoming calls?
• Is it only for voicemails?
• Does it only happen for calls involving specific callers/callee's?

 

[TLCtech]

So that sounds like its related to our audio issue.

The Pi4 is the pi 4. I dont understand how it would be undervolted unless its like that out of the box. I could try and overclock it but it doesnt look like its necessary.

It happens randomly to almost all users.
Incoming and outgoing but the VM is a different issue than our audio issue. At least it sounds different. The audio issue we have is where audio just drops for users, usually outgoing. Someone mentioned it, either here or elsewhere, and I contacted our ISP and the confirmed it,. But now I cant remember the specific parameter that its dropping on. I have a hunch its related, but since its a different symptom, I wasnt sure.

My power users are the ones who complain. But this VM issue seems to happen to all users. This was forwarded by someone who doesnt use the phone much at all.

Would packet drops cause this?

 

[VoIPTools]

I would get a packet capture and send it to technical support. for review. That will help identify if it is an audio issue or a hardware issue.

 

[TLCtech]

FOUND IT!
RTP Jitter of 64
Callcentric saw it
Would that affect how voicemails are saved?

 

[VasilisV_3CX]

Hi @TLCtech,

@VoIPTools is correct. Start a packet capture and call in to the system, leave a voicemail and stop the capture. This way you will be able to check where the audio problem is coming from, from the provider to the PBX or from the PBX to the file. If you require assistance troubleshooting this, I'd contact 3CX Support to investigate and assist.