IP Phone does not play busy tone on PBX phone busy

Unanswered Question
Nov 27th, 2011
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I have a H.323 gateway connected to a legacy PBX device via ISDN E1. Calls are working ok but the user epxerience is when the second call goes through to the same PBX extension is not a busy tone but the annoucment stating that the call cannot be complted as dialled and to check the number. The Q931debug does report User Busy so just a bit unsure why CUCM does not pass busy tone to the phone.

Looking at the cause code from the PBX Side I see 0x8191, user busy (CUCM plays annoucement)

Looking at the cause code from the PSTN Side i see 0x8491, user busy (CUCM plays busy tone)


81 = the private network near the local user (possibly a local private           branch exchange [PBX])

84 = the public network near the remote user (remote telco           switch)

only non default item under the pots dial-peer is:

tone ringback-alert-noPI


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acampbell Mon, 11/28/2011 - 02:46
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Can you try adding the following to the global config


voice rtp send-recv

voice call convert-discpi-to-prog





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