Delay between picking up call and being able to talk

[Muyz]

Hi there, my name is Milan and I just joined this forum. Have been using 3CX for some time now for small business purposes. There is one (major) issue that almost makes me pull my hair out: there is a varying, but most of the times significant delay between picking up a call and being able to speak. The delay is up to about 5 seconds.

Since I thought it might have to do with the server running on Win10, I installed everything on Debian 9 tonight; standard annual 16.0.3.676. Same thing happens.

Delay is larger when calling a ring group (either prioritized hunt or ring all; three members) compared to calling an extension.

Hosting is on premise; NATted; firewall checks okay. Voice quality is great. Clients are all soft-phones running latest version of 3CX app. Soft-phones are iOS as well Android based. Same problem on all phones.

Does anyone already have a clue based on this information? Probably, I am not mentioning things you need to help me out. Please tell me. Thanks.

 

[Alphabetic]

Is this all calls?

Does it happen on internal calls too?

what is your trunk provider?

 

[JohnS_3CX]

Hi Milan,

The clients need to get a push notification to ring. Try the webclient and compare the performance between the two. Is the webclient always fast and the mobiles always have a delay?

We are talking extension to extension calls now to evaluate the internal network. Also, make sure the machine is powerful enough to run your setup
https://www.3cx.com/docs/recommended-hardware-specifications-for-3cx/

 

[Muyz]

Is this all calls?

Just tried a direct call, i.e. not a ring group and there was a considerable delay. Caller (me) heard phone ringing about 7 times, callee answered upon first ring and I was told setup of the call lasted between 5 and 10 seconds. I was calling on 4G via 3CX app to callee inside the PBX local network, so extension<->extension.

Does it happen on internal calls too?

I'll try this evening.

what is your trunk provider?

CheapConnect.

The clients need to get a push notification to ring. Try the webclient and compare the performance between the two. Is the webclient always fast and the mobiles always have a delay?

We are talking extension to extension calls now to evaluate the internal network. Also, make sure the machine is powerful enough to run your setup

Will try the web client this evening.

The delay is also there when I make a regular phone call to the extension (i.e. not via 3CX app).

HW is an Intel NUC 8I3BEH2 / 16GB / 250GB M2.SSD. That should do the trick, I guess.

 

[AWS2P]

Hardware ressource are they comfortable?
No SIP ALG on router /firewall?
Firewall checker passed green ?

 

[Muyz]

Hardware ressource are they comfortable?
No SIP ALG on router /firewall?
Firewall checker passed green ?

Yes, no HW stress (see previous posting for specs). No SIP ALG and all firewall checks pass.

 

[AWS2P]

NUC is installed now on Debian 9 with 3cx iso ?no drivers problems?

Use of NUC is dedicated to PBX?

 

[Muyz]

NUC is installed now on Debian 9 with 3cx iso ?no drivers problems?

Use of NUC is dedicated to PBX?

Indeed, I used the 3CX ISO for installation. NUC is dedicated to PBX.

 

[AWS2P]

ISP line is good enough , bandwith, latency?
Are they using WIFI ? or only 4G ? or on automated mode so it can be one or the other?
LAN is with VLAN ? everything connected to GB ports?

Have you tried a wireshark capture?

 

[JohnS_3CX]

How does the NUC connect to the internet? Ensure it's WiFi adapter is disabled. The PBX should only see a single adapter in the system

 

[Muyz]

ISP line is good enough , bandwith, latency?
Are they using WIFI ? or only 4G ? or on automated mode so it can be one or the other?
LAN is with VLAN ? everything connected to GB ports?

Have you tried a wireshark capture?

1Gbps ISP connection on WAN, latency <7ms. Either 4G or WiFi. Problem with both. No VLAN. Problem present when using NUC on Gb ports. No wireshared capture yet.

How does the NUC connect to the internet? Ensure it's WiFi adapter is disabled. The PBX should only see a single adapter in the system

On Windows, I had all BT, WiFi, etc. interfaces disabled. Problem was there. Now, with the Linux install, I forgot to disable other adapters. Will do so this evening (gonna be a busy night ;-))

 

[AWS2P]

Which CPU Is on the NUC, is ethernet port intel based?

May be a setting in network card, do you use Jumbo Packets? see intel
https://www.intel.com/content/www/u...0005593/network-and-io/ethernet-products.html

Do you use IPV6 ?