NO JOY Remote Phones - Unreliable Audio

[jjohnson911]

Hello,

Hoping someone may have some advice for remote phones that we're having trouble with.

It appears at this point to be a bandwidth/reliability issue on the remote phone end, but I want to be sure there is nothing else on our end that could be causing the issues our staff are running into.

Our remote phones connect to the server through openvpn to limit the port exposure to the outside world.

From time to time, the remote users will have a 15-20 second gap in audio, where the person on the other end hears silence, then all at once the audio all comes through in a sped up fashion so that the user sounds like a chipmunk.

Any ideas on things we can check out or try to fix this?

Considering just paying a consultant to review the overall setup from the server to the routers as well, just not sure if i'm there yet.

Thanks in advance for any thoughts you may have!

Josh

 

[rjaiswal]

Couple of questions... How many concurrent openvpn connections are you hosting? What kind of device is hosting the openvpn server? What encryption algorithm are you using?

 

[jjohnson911]

Couple of questions... How many concurrent openvpn connections are you hosting? What kind of device is hosting the openvpn server? What encryption algorithm are you using?

Encryption is AES-128-CBC

Same server is hosting PIAF and OpenVPN

9 - 10 connections at any point in time to the VPN, 2-3 concurrent calls over the VPN max. 30 total extensions on the system.

System has an intel xeon, 4 core, 2.4 GHz processor, 4 GB ram, seems to never really go over 5-10% utilization.

 

[rjaiswal]

Have you tried adjusting the Ethernet buffer size? I found an article that shows how one would adjust advanced network settings.

http://www.nateware.com/linux-network-tuning-for-2013.html#.U35EPzi9KK0