Inbound PXO - Dahdi config - Terminating calls from FreePBX and it doesn't on other end

I have recently purchased a OpenVox A400E01 with 2* FXO modules for my Asterisk - FreePBX system. I have a “catchall” inbound route which is then sent to a specific extension. This all appears to work OK.

However I have an issue when I terminate the call from the extension on my Asterisk box the analogue line stays open until the caller terminates it.

I have had a look around and I get the impression it may be to do with some regional settings but I am not totally sure what I should be looking for…

Any help would be appreciated, I am based in the UK if that makes any massive difference.

Cheers in advance

This is normal behaviour for a UK analogue line, although BT have supposedly reduced the timeout from about 3 minutes to a few tens of seconds, just this year. It was done so that you could hangup the call on one parallel wired extension and pick it up on another. The only real solution is to use ISDN, directly, or via and ITSP. ISDN distinguishes between a network CLEAR and the final RELEASE,

For more details, search for BT’s SIN (Supplier Information Note) on single line analogue connections.

It is also done in some, if not most, other countries.

It is the basis of one telephone based confidence trick.

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Thanks for the reply, is there no way to tell FreePBX to go, oh you have put the extension up now lets just hang up the call?

Something like some AGI script?

This is a limitation of the service you have bought from the PSTN operator, not the PABX. You can only generate CLEAR signals on an incoming analogue PSTN call. Only the network, or the calling party, cannot generate a RELEASE signal. See section 7.1.2 of

The PABX has only one way of hanging up an analogue call and that is to remove the loop across the A and B wires. This generates a CLEAR indication in the network. It will already be doing that.

(I believe the reference to 2 seconds is a recent change, and the minimum used to be much longer. I believe all UK network operators have a delay between called party CLEAR and network RELEASE.)

Mobile phones may interpret the CLEAR as a hold.