In the the following situation, the called party does not send a BYE message when he disconnects from 3CXPhone in Windows, both version 5 and 6. All else works just fine, sound, DTMF tones, conversation,... User-1 dials the remote server which runs a Dialogic HMP PBX. User-1 presses 7 to be able to select the user to dial in the IVR. User-1 presses the 4 digit number of the user to dial. User-2 receives the call from User-1 and picks up. User-2 presses 8 to stop the information message from the server. User-1 is now connected with User-2 and they talk. User-2 hangs up ⇒ No BYE is sent. User-1 does not hear anything any more so hangs up. ⇒ BYE is sent to the server. (Normally User-1 drops back into the IVR and can do other stuff) The server sends a BYE to User-2 as part of the cleanup procedure. This has been tested where all 3 parties are in different cities. I attached Wireshark log files from both the server and the users pc (not the same calls) where User-1 calls to himself , which has the same result and has the benefit of having all data in 1 log file. Is this a 3CX Phone bug or is there a setting I need to adjust ?