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Community Member

External calls not connected


I'm having difficulties with outging calls - some calls, from some phones(randomly), are not connected - the LCD shows call proceed but there is no ring tone, no voice transmission. When you try to dial the number again the call is usually connected immediatelly. We are running CCM 4.0(2a)sr2c with phone load 7.2(4.0) - after the FW upgrade, I have the feeling that it's not that common but still happens (several times a day).

I also tried to search the log, but did not find anything suspicious.

Any post/ideas are highly appreciated.

Best regards,



Re: External calls not connected

Could you please post CCM traces and if possible debug isdn q931 (if using MGCP) of the failing call to see what is happening.

Community Member

Re: External calls not connected


sorry for not answering faster, but we wanted to update the IOS on the router and see whether it helps or not. It did not hovewer. We are using H.323 for the signaling between CCM and the GW.

I tried to make the log file smaller so I've deleted all other calls from the log (or at least a majority of them).

Thank you all for any suggestions / ideas.


Community Member

Re: External calls not connected

What is the GW here?

I have had a similar situation where the calls were connecting, so the signaling was good, but had one or no-way audio. Once I found the signaling working, I ruled out the CM as being an issue.

In my case, I was using a 2600 with a NM-HDV connected to a PRI. I found that I had bad DSP modules in this NM-HDV which caused the audio to inconsistantly fail. I'm not sure that this is your case, but thought I'd offer advice from a similar situation.

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