Unable to dial out after transferring a call

I have an installation that is using FreePBX Distro 2.210.62-3 with Asterisk 1.8. The installation has 2 POTS trunks connected to a Digium TDM410. The card has 2 line modules installed and a hardware echo canceller. There are 5 Polycom SoundPoint IP321’s as extensions.

When a call comes in, the receptionist transfers the call to whoever it is for. At that point, she’s unable to make an outgoing call, even though the other external line is still free. She can’t call out until the other call is terminated. I’ve run some tests and no matter which phones they use, once a call has been transferred, the original destination is prevented from dialling out while the call is active.

I can’t see why this is happening, because I’d assume that once the transfer completes, the original extension is no longer part of the call and shouldn’t be affected by the call-in-progress.

Has anyone seen this before? Any ideas what could be causing it?

Tim Long.

What do you gave for destination in your outbound route? You need to either explicitly state the channels, one per destination or have the two ports in the same group and send the call to the group.

I have configured the DAHDI trunks as 2 seperate trunks, which I call ‘Line 1’ and ‘Line 2’.

In the outbound route, I listed ‘Line 1’ and ‘Line 2’ in the trunk sequence.

This does seem to work under most circumstances, for example if there is already an incoming call on Line 1 then a new oubtound call will go out on Line 2.

The problem only comes when an incoming call has been transferred. It sounds odd, I know, and I haven’t seen it before. I will gather some dial plan diagnostics on Monday and maybe post them here.

Where is the call being transferred to? Is it an internal extension or possibly out the other trunk?