I have 3825 CME with CUE, when a caller call and the autoattended played and route to whatever extension he want, and the caller hang-up before answering the phone keep ringing with no end.
I tried to configure the FXO to one of extension directly without autoattendant it worked fine “disconnect directly”.
I have attach you “show run” and “debug vpm signal”
If you need the detail screenshot for each steps, you can check this link:
Hope this help