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One way audio

One way audio

One way audio

I have a customer that has two locations linked together with internet T1's using Kentrox Q-series routers and VPN.  There is rarely a sound quality issue.

Problem:  Every time a call is placed or recieved by an extension, and that extension either puts the call on hold or transfers it to another extension there is one way audio.  

We also have a similar problem with our office NBX.  Remote extensions are connected via SDSL to a 3COM 3CR870 router with 3COM 3CR858 routers using VPN.  Same problem.  

Both systems use IP on the fly.  I thought the problem was due to ARP flush times, but both use 3COM 4400 switches and ARP flush time is non programmable.  

I have two more sites like the first one going in next month and I must find a solution.  Can someone please help?

RE: One way audio

I haven't run into this but I have hear of this. When a call is sent to a IP phone, the phone system tags it for QOS. When the person on the IP phone end starts talking a system needs to mark the packet as QOS. This is a big problem with most systems. The phone itself doen't send that communcation, from it's end, marked for QOS. They have been working on this so maybe a few have worked it out.

I hear more and more about this problem as we get closer to a large install of VOIP.

RE: One way audio

i am trying to setup a remote office with my nbx 100. i can hear the audio prompts on the system but no voices and they can not hear me either. Using Ip on the fly. Should the remote phone get ip addresses for my local network in the remote location or should it get an ip on the work network. i do have a vpn setup to the laptop and the tunnel works fine but the phone doesn't i can call them phone rings they answer hear nothing at all. i can call my cell phone hear nothing except it i push the keys then i hear those but no voice at all?????

need help please

RE: One way audio

I got the same problem between two sites using IP on the fly. Sometimes it works but most the time one site can hear you but you can't hear them. It is really strange. I have this problem when I call the other site through VTL. I assume everyone is using VTL when they encounter this problem.

RE: One way audio

I have identical setup as you have with 2 kentrox routers and 3Com router on anothe branch office. After talking to Kentrox and 3Com tech support, we finally found out the problem. We are not suppose to use IP on the fly with kentrox router or some brand router because ARP table issue that Kentrox aware of. The solution is to make the NBX using standard IP and hence you need to configure manually the IP address for all phone stations. Since the changes to Standard IP, everything is working fine, no more one way communication.

RE: One way audio

Yeah we did the same thing.  Changed to standard IP, manually assigned IP's and this cleared the problem.

RE: One way audio

thank you all for the feedback. I just have few questions,    Do we have to change all the sites to standard IP? Let say I have 5 sites( all sites has NBX) one is using IP on the fly and the other 4 is converted to Standard IP. Will this work or should I have to convert all to Standard IP? How about the line cards and analog cards, should I assign an IP as well. I hope this will also fix our problem. Thanks again.

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