FXO remain connected even though local phone hung up

[sdeltoro1]

phone "a" is conected to pbx "a" and this to the to router "a" via fxo. router "a" to router "b" via voip, and router "b" to pbx "b" via e&m and pbx "b" has phone "b".

The fxo on router "a" remain connected until phone "b", hung up. But if I make a call and phone "a" hung up, the router "a" remain connected until phone "b" hung up.

I run the debug voice ccapi inout on router "a" and I can?t see when phone "a" hung up, only when phone "b".

[kc-ussugar]

Try changing FXO port from "ground start" to "loop start" or vice versa.

[sergey.zelenev]

You have a problem with FXO detecting a supervisory disconnect

Find out what signalling and method of disconnect your PBX is using and configure the FXO on the router accordingly.

The following links might help:

http://cisco.com/en/US/tech/tk652/tk653/technologies_tech_note09186a00800ae2d1.shtml

http://cisco.com/en/US/products/sw/iosswrel/ps1834/products_feature_guide09186a00801601ac.html