Call disconnected whrn call off-hook between CUCM-IP Phone

[Ritesh Desai]

Hi

I am having a problem whereby calls coming in from the SIP Trunk are being dropped on lifting up the handset. 

Scenario-1: Outbound call -  IP Phone to Mobile. RTP Session is established. Successful

Scenario-2: Inbound call - Mobile to IP Phone. RTP Session is established from Mobile to Audio Codes. IP Phone rings. When Ip Phone is off-hook call disconnects. 

This is a fresh installation of CUCM.

Is der issue between AudioCodes to CUCM else between CUCM - IP Phones....?

Do you have any suggestions on what this could be ?

Call Flow is 

PSTN > Audio Codes ( SIP Gateway) > CUCM 10.5 > IP Phone.

[Manish Gogna]

Hi Ritesh,

If the call is disconnecting as soon as you go off hook then it is most likely a codec mismatch issue. You can check if the region settings between IP phone and SIP trunk and also the codec on the dial-peer on CUBE is set to G711. In that case a transcoder will not be required, else if one leg is g711 and other is g729 then you will need to configure transcoder.

HTH

Manish

[Ritesh Desai]

Hi Manish,

Glad to hear your response. As I hv mentioned there is no CUBE in this scenario.

Point1: There is no CODEC mismatch.

Point2: As i read, region config is not reqd unless difft CODEC is used.

Is there any otha place of start troubleshoot.

[Manish Gogna]

What is the SIP Trunk destination address pointing to?

If the phone rings and call disconnects when phone goes off-hook, you need to collect detailed ccm traces for a test call if codec is not an issue. The SIP signaling in the traces can tell where the issue is.

HTH

Manish

[Ritesh Desai]

Thanks Manish,

I have attached CUCM Trace logs. Please guide me through troubleshooting procedures. Manish will you please help me in undersanding Region, Audio Codec pref list config and Device pool. Am not getting it.

regards,

Ritesh Desai