In an ad-hoc conference if one external member leaves, the remaining members are hearing a busy tone.
We are using CUCM 7.1(3a) and a 2821 router as the H.323 gateway to PSTN.
This gateway is also the conferencing bridge.
In this context I notice when at the end of an external call TO an IP phone the external party hang up the call releases immediately after the DISCONNECT signal.
At the end of an external call FROM an IP phone the IP phone user gets a busy tone when the external party hang up. The RELEASE signal occures 40 seconds later after receiving the DISCONNECT signal.
Are there any configuration tasks in CUCM and/or gateway to change this behavior, so that at "normal call clearing" the call will be released in any case.
For your information:
I issued the voice call convert-discpi-to-prog command as described here because we don't hear the announcement if the called party number is out of order.