Stuttering on second call

[jonathanc]

I have a problem when making or receiving a second call on my system, whether from the same phone or using different phones.

The quality of the first call is superb; but when the second connects. both calls begin stuttering to an unacceptable extent.

I am using 3CX v 10 (until i am sure the system is right for me) with Cisco SPA 303 phones - latest firmware.

The problem is the same with both Draytel and Sipgate as service providers.

Sipgate suggested I use 'sipgate.co.uk' as Proxy and Outbound proxy on my phones, and my Sipgate account credentials for User ID, Password and Auth ID. I tried this, and was able to make simultaneous calls which did not stutter. But then, of course, the calls were bypassing 3CX altogether and I lost all PBX functionality! Restoring the above parameters to reflect the extension settings in 3CX (as per http://www.3cx.com/sip-phones/ Updated link) brought the problem back with it.

The relevant part of the Server Activity log (with details changed to protect the innocent) are as follows.

22:07:01.779 [CM503008]: Call(24): Call is terminated
22:06:59.223 [CM503008]: Call(23): Call is terminated
22:06:36.758 [CM503007]: Call(24): Device joined: sip:[email protected]:5060
22:06:36.755 [CM503007]: Call(24): Device joined: sip:[email protected]:5262
22:06:34.246 [CM505003]: Provider:[Sipgate Church] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [] PBX contact: [sip:[email protected]:5060]
22:06:34.245 [CM503002]: Call(24): Alerting sip:[email protected]:5060
22:06:32.737 Currently active calls - 2: [23,24]
22:06:28.897 [CM503025]: Call(24): Calling VoIPline:07828510xxx@(Ln.10007@Sipgate Church)@[Dev:sip:[email protected]:5060]
22:06:28.057 [CM503004]: Call(24): Route 1: VoIPline:07828510xxx@(Ln.10007@Sipgate Church)@[Dev:sip:[email protected]:5060]
22:06:28.055 [CM503010]: Making route(s) to <sip:[email protected]>
22:06:28.052 [CM505001]: Ext.107: Device info: Device Identified: [Man: Cisco;Mod: SPA Series;Rev: General] Capabilities:[reinvite, replaces, unable-no-sdp, no-recvonly] UserAgent: [Cisco/SPA303-7.5.4] PBX contact: [sip:[email protected]:5060]
22:06:28.051 [CM503001]: Call(24): Incoming call from Ext.107 to <sip:[email protected]>
22:06:11.801 [CM503007]: Call(23): Device joined: sip:[email protected]:5060
22:06:11.799 [CM503007]: Call(23): Device joined: sip:[email protected]:5261
22:06:09.454 [CM505003]: Provider:[Sipgate Personal] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [] PBX contact: [sip:[email protected]:5060]
22:06:09.453 [CM503002]: Call(23): Alerting sip:[email protected]:5060
22:06:06.006 [CM503025]: Call(23): Calling VoIPline:01994419xxx@(Ln.10006@Sipgate Personal)@[Dev:sip:[email protected]:5060]
22:06:05.167 [CM503004]: Call(23): Route 1: VoIPline:01994419xxx@(Ln.10006@Sipgate Personal)@[Dev:sip:[email protected]:5060]
22:06:05.166 [CM503010]: Making route(s) to <sip:[email protected]>
22:06:05.163 [CM505001]: Ext.106: Device info: Device Identified: [Man: Cisco;Mod: SPA Series;Rev: General] Capabilities:[reinvite, replaces, unable-no-sdp, no-recvonly] UserAgent: [Cisco/SPA303-7.5.4] PBX contact: [sip:[email protected]:5060]
22:06:05.161 [CM503001]: Call(23): Incoming call from Ext.106 to <sip:[email protected]>

One of the 'outside' phones is obviously a mobile in this case, but the same thing happens with two landlines involved.

Is there something there which is glaringly obvious to everyone else but invisible to me, please?

 

[lneblett]

Yes, satellite is killer on the latency.

On a slightly different note -
We always suggested a bandwidth problem as the symptom complained about is almost always network related. For the most part, and don't take offence, folks only think they know what the loading is at any given point, when in fact they don't. The network is largely comprised of a number of different physical devices and cables anyone of which could be impacting the ability of the network to operate optimally. Further, there are background tasks and communications that occur that we oftentimes forget about and then there are the issues such as yours where you have an asymmetrical interface 20/2 handling a symmetrical stream need. The one thing that I do not recall our having suggested is to check the NIC cards or interfaces and ensure that they are not compromised. I did a factory reset to one device and installed the latest firmware only to discover that it set itself to 10Mbs half-duplex for some reason.

In any event, glad all is working.