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New Member

Crackling voice over ip phones

I have a Call Manager ver 4.1, phones are 7960 series. I have a 6506 switch in the MDF and three IDFs, each with 4506 switchs. Two of the IDF locations, the phone calls between all ip phones and ip phones and pstn phones are excellent sounding. For the past 3 months, quality between phone calls have been great. We created a new IDF and moved phones from other areas to this location. The IDF is connected back to the MDF with single-mode fiber. When calls are placed this past week, people on the other end, whether they have a pstn phone, ip phone, internal call or external call, complain that our voice is crackling, echoing, chopping up, etc, but their voices are excellent. This doesn't happen all the time. We rebooted the switch and is mostly cleared up, but as the conversations continue, the quality goes down. If we hang up and try again, it gets a little better. This quality happend a few weeks back and got worse. We are concerned, that it will get real bad again, like this past week.

Does anyone happen to have any explanations or cures?

Thanks for your time!



Re: Crackling voice over ip phones

Make sure that the QoS config on the new 4506 matches the ones that are working well. If you would like to post the configs, we can take a look at what might be causing the problem.



Re: Crackling voice over ip phones

During call press i (info) button to see if there are excessive packet drops.

New Member

Re: Crackling voice over ip phones

Thanks for your help. I think we found the problem and we will be testing it today. It looks like the ports were configured for phones to be used as switches, not just voip. Thanks again.