PROBLEM DESCRIPTION: Experienced a scenario where a client had an analog doorbell device connected to an FXS port on an AudioCodes Mediant 1000 gateway, which rings a number assigned to Microsoft Lync user. The Lync user is able to answer the call, but when they hang up the call it continuously rings again until the doorbell is pressed again.
In testing/troubleshooting this issue, we connected an analog phone to the FXS in order to simulate the behavior. When the analog phone goes off hook, it automatically dials the Lync user. The Lync user answers successfully and hangs up. Because the analog phone is off hook, it rings the Lync user again until it is placed back on hook.
After going through many troubleshooting steps as follows:
- Modified the analog parameters section of the configuration file as advised.
- Deleted the call progress tone file from the Mediant under Maintenance -> Software Upgrade -> Load Auxiliary Files.
- Uploaded the provided <LANGUAGE>.dat file.
- Update the firmware version to the newer release that is the same as tested by AudioCodes support.
CAUSE: We narrowed down the issue to being that the Analog device is not disconnecting after receiving the reorder tone. Found out that it iss because of "Enable current disconnect" parameter is enabled. Usually it shouldn't affect FXS port, but we see it gives some impacts on FXS port.
RESOLUTION: Go to Configuration->VoIP->SIP Definitions->Advanced Parameters and set "Current Disconnect" parameter to Disable.
If you have FXO cards installed in the AudioCodes gateway, change Configuration->VoIP->GW and IP to IP->Analog Gateway->FXO Settings > Reorder Tone Duration [sec] : 2 Sec. If not, go to http://<IP Address>/AdminPage, click on INI Parameters, and enter:
Parameter Name: TimeForReorderTone, Value: 2
BURN configuration and test with Analog phone. I am pretty hopeful that this will resolve the issue, atleast to Analog phone.
Now when the Lync user hangs up the call, you should hear BEEP BEEP on analog phone. That BEEP is reorder tone to notify analog side user that Lync has hung up the call. That BEEP comes from call progress tone file loaded on the GW. The analog phone should be disconnecting correctly now.