NIC Team Caused Voice Delay Issues

[Justin Richter]

All,

I wanted to put this out there. I had some weird delay issues at a site. I found if the soft phone was used connecting directly to the PBX there was no delay. However, if the desk phone was used connected through an SBC there was a large delay. I logged into the phone and ran a ping against the SBC and found DUP! packets were coming back. The SBC is on a virtual server behind a NIC Team. I removed two of the three NICs from the team and the delay disappeared. Very strange!

 

[cobaltit]

Windows? Linux? Version? NIC type?

 

[Justin Richter]

This was on a Windows Server 2012 R2 Standard Host. The SBC is on a server running Windows 2012 R2 Standard as well. The NICs are Intel Gigabit 4P I350s.

 

[eddv123]

I'd advise a switch to web client and see whether you get the same results, web client is the main direction for 3CX development now.

 

[cobaltit]

I'd advise a switch to web client and see whether you get the same results, web client is the main direction for 3CX development now.

? The op was having audio issues with desk phones, not the soft phone. The web client is the direction for the soft client but desk phones aren't going away anytime soon.

 

[eddv123]

@cobaltit thanks for the correction, I completely mis-read this.

So in the case of it being IP handsets the only thing that springs to mind is something on a network level.

Both SBC and software phone use port 5090/3CX tunnel however the phones must connect to the SBC first via the local network.

Before even discussing the SBC/NIC side of things you may want to also check the local network- i am talking specifically at the switch, uplink, QoS, VLAN level here.

I had a similar issue recently, however this was down to the 3rd party IT making certain network changes and not feeding the information on to us.

 

[diamond9]

Not sure if you got this sorted yet, another thing to take a quick look into is VMQ on broadcom adapters, we had a major issue with this on a customer site, on the host server run
Get-NetAdapterVmq
if you get any results run
Set-NetAdapterVmq -Name "NIC Name" -Enabled $False

 

[cobaltit]

The NICs are Intel Gigabit 4P I350s.

Not the case here but good point. It is listed as something to check on the 3CX HyperV guide:


https://www.3cx.com/docs/installing-microsoft-hyper-v/

 

[diamond9]

Not the case here but good point. It is listed as something to check on the 3CX HyperV guide:


https://www.3cx.com/docs/installing-microsoft-hyper-v/

Sorry i totally missed that point - my bad

 

[cobaltit]

No worries.. good point though.. catches a lot of people, myself included the first time.