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New Member

FXO port not releasing calls that have hung up

We have cme in the Kansas City Area and every few weeks we get FXO ports that will not release the line its when a user hangs up. the issues clears for a couple weeks after i do a shut/no shut on the FXO interface. i'm trying to figure out how to stop this from happening.

I am running CME 10.0 on cisco 2901 running 15.4(2)T

Here is my config on all the voice ports

voice-port 0/X/X
 trunk-group ALL_FXO
 output attenuation -2
 connection plar opx XXXX
 description XXX-XXX-XXXX
 caller-id enable


At this point i have not seen any pattern on which ports this happens to.


Hi,I don't know how are the


I don't know how are the lines in US. But here in Spain, you must configure the "battery-reversal" command on every FXO port. The PSTN send to the customer a polarity change to notify the call end....

You can try it.... I hope to help you!!



VIP Gold

apart from David (+5)

apart from David (+5) suggestion, you can try to give below command under voice port.

timeouts wait-release 1



Thanks for your +5!!!  David

Thanks for your +5!!! yes



New Member

i will try it however it

i will try it however it could be a few weeks before i know if it worked

New Member

 There are some debugs you


There are some debugs you can use to detect which type of disconnect supervision your TELCO supports, and configure accordingly. 

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