Got an issue with a line that the Telco says is ok. Got three trunk lines going into the FXO card. One line constantly holds the FXO port off hook. It may occasionally remain on hook if it is disconnected but after the first call it remains off hook again. I have switch the line across all 4 ports of my FXO card and it does the same on all 4 ports. I have also swapped the other two working lines across the ports and they are ok across all 4 ports. The Telco has tested the line and made and received calls with their test phone so they are convinced the line is ok. I have attached a debug vpm signal port 0/3/0 is a working port and I can see it going down and then coming backup and remaining on hook. port 0/3/2 has the faulty line and that goes off hook after coming back up. Is there any other way I can prove that the signaling coming from the line is wrong so i can go back to the telco.
Help much appreciated