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!
John
