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?