I have a site where a standard POTS line is connected to a 2851 router FXO port. This is an MGCP gateway.
The problem I have is that when I call the number (10 digit) and leave a voice mail, about 10 seconds later the phone rings from an unknown number.
Troubleshooting steps taken:
1) I thought it may be an FXO disconnect problem. Changed port to ground start
2) Disabled supervisory disconnect
After attempting both of these, the issue is still happening. Any advice is greatly appreciated.