Choppy Incoming Voice

[vincelarkin]

Hello,

Just upgraded to the small business edition and having some issues with call quality.

We have turned off all other computers using out broadband connection and when we receive a call the customer can hear us perfect but we are having real trouble hearing them. I would have thought that the downstream being the highest rate would have no problems and the upsream being the one to loose quality.

Vince

Also I cant seem to find the PC specs for the software. Spped / RAM etc.

 

[amygoda]

Hello,
after call connected 3CX system not reposable for any thing because in sip system the connection will be between the 2 devices
to be sure you canshut down the server while the call and the call will not be ended
so you have to check your devices,bandwidth and try to use g729 codec

 

[vincelarkin]

I will try that.

Strange thing is that we have the 3cx computer on win xp with remote desktop.

If I'm on a call and I initiate the remote desktop connection then the call breaks up even more until the RDP is fully connected and the desktop is shown on my PC

 

[galal202]

Hello,
thats mean your internet connection speed not enough
also remote disktop works even you are not work

 

[vincelarkin]

I've done some testing.

Made an internal call from one extension to another and the reboot the 3cx box and the call stays active.

So did the same with a call in from my mobile and the call was dropped.

Went in to the settings for the external line and disabled "PBX delivers audio" and still the call was dropped on reboot.

Any ideas? What's the issue with postgre ?

 

[vincelarkin]

Yes the external call is going via voip provider

 

[galal202]

ok your extrenal call depend on you internet connection
but internal call is local
if you have 3cx smb lic you'll have g729 to external calls

 

[h2009]

Have you tried to use another provider - i found that some providers are bad at delivering audio.

 

[NetworkLabs]

3CX is working as designed, you are confusing media server proxy mode (which you have) with transcoding mode “PBX Delivers audio” (which you only need if using differing codecs) Because one of your endpoints and the 3CX PBX are on the same network (hence proxy mode) you may well be suffering with the 3CX host machines lack of resources.

Also SIP trunk providers do make a big difference, all depends on what they do with your traffic after it leaves your network, in theory call quality should be dependant only upon the codec, the networks involved, the carrier and its QOS.

If you want to eliminate the 3CX host machine from your audio streams you have to have both endpoints on the same network (you tested that and it worked fine)

SIP PBX media servers are basically voice routers using routing protocols (SIP) for routed traffic (RTP)

So for call quality check in order: -

Users/testers expectations/presumptions
Packet flow (latency, loss and jitter (MOS))
Bandwidth available (to be sure 50k g729, 100k g711)
3CX host resources
Codec overhead (resources other than bandwidth)

All this is why we provide 3CX via a managed appliance and manage our own SipRoutes…VOIP is an art 8)

 

[vincelarkin]

Ok It turns out that the non free version of 3cx needs more computing power.

Before we upgraded to small business version everything was ok. Then the calls were choppy (downstream only) I moved the 3cx to a more powerful computer and everything works great now.

The old system had a 1gig CPU and 1gig ram