double latency when using Softphone

[jampy]

I'm experiencing 2x to 3x the latency when using the 3CX softphone compared to a hardware VoIP phone. Zoiper ist better, but still at 2x the latency compared to the hardware phone.

Hardware phone is a Grandstream GXP2170, provisioned by 3CX. I measure about 220 ms roundtrip (acceptable to me) time (to *777) with that phone. It shows codec G772 is in use.

The softphone is installed on a brand new, high end DELL XPS 17 (10th gen Core i7) and I measure at least 460ms roundtrip. I've experienced the same latency on my prior laptop.

Both devices are connected to the same Gbit switch by wire, so I don't think this is network related.

I get similar (bad) results when using the 3CX client on my Android phone (not much difference between WLAN and mobile network).

3CX Professional is installed on a cloud server with PING times min 19ms, max 80ms, avg 19ms and zero packet loss (over 630 packets). There is only one 3CX extension in use.

I did lots of research to try to solve the problem myself, but I can't figure out why the softphones have such a high latency. Can anyone please give me some advice?

 

[JohnS_3CX]

Hi jampy,

I would start by asking what methodology did you use to measure the roundtrip?

I think this question is more important than anything, so please provide as much detail as you can.

 

[jampy]

Hi JohnS_3CX, I made some sounds (like finger snapping) and recorded the original sound and the looped back sound from the loundspeaker using Audacity, which reveals the temporal difference using the selection tool.

This is using the Grandstream:



This is via 3CX Softphone under Win10:



I've attached the Softphone recording.

Please let me know what else you'd like to know.