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No Audio on PRI Calls

Hey everyone. I will try to keep this short, but supply as much information as possible.

On june 28th, and again today on July 5, we have had this issue:

If you are outside, and call in on a line that comes in on our PRI, the person receiving the call cannot hear you at all. Yet you can hear them perfectly.

If you are outside, and call in on a line that comes in our PRI with an automated attendant, no input is accepted. (i.e. Press 1 for this, 2 for that, if you press a key, the greeting just keeps going. If you dial an extension, the greeting just keeps going).

If you are inside, and dial out (we use a 9 to get an outside line, this puts you out on the PRI), the phone will show that the call is connected, yet you cannot hear anything at all. No phone ring, nothing.

Today, I pressed 9, and dialed the automated weather phone in town, I got connected to an Engineering firm 15 miles away. I hung up, dialed the same weather phone, and got the very same Engineering firm 15 miles away. In both cases, the person on the other end could not hear me.

Also today, occasionally I would pick up my handset, and be right in the middle of someone's phone conversation.

In both cases, if you call in to a line that is POTS going into a 2801, you are fine. And if you call out using a POTS line, you are fine (even though the POTS outbound line is on a 2801).

All this led me to believe it was a phone company issue, yet the assure me it was definitely not. I had not rebooted my CCM in over a year, so I rebooted it today. Both instances, in less than an hour, things go back to normal, but needless to say, the issue is killing me! Where would I start to look for ideas on what is happening??

My CCM is a 4.2sr5a

2801 w/PRI is 12.3(11)T9 MGCP


Re: No Audio on PRI Calls


CCM 4.1(3)sr5a...I think...

1. One way audio.


mgcp dtmf-relay voip codec all

You may open a TAC case for further analisys.

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