Attended Transfers queue to queue


I’m brand new here. I am running Asterisk 13.4 and FreePBX 12. Most of my dial plan logic is done outside of FreePBX, as I mainly use FreePBX for provisioning and maintaining extensions. We just migrated from a Nortel Option 11c. My problem lies in transferring between queues. I have a complex IVR application that I wrote, that interacts with an iSeries As400 via ODBC, and it can transfer calls out to two different queues. One for Customer Service for accounting information and one for Help Desk for technical support. There are several calls per day that get into the wrong queue (because they’re “power users” and mash buttons to get to a human). The company policy is no transfer can be done blind. On the Nortel system, they were able to dial up the extension for the other queue and initiate a transfer, and get a rep on the phone and inform them of the transfer, and then transfer, and the other party takes the call. On the Asterisk, these transfers are about 50/50 reliable. They get the other party, and inform them of the transfer, and then 50% of the time the transfer goes through, and the other 50% the line just hangs up. They can transfer to a direct extension with 100% success. These calls coming in from the outside are coming in over PRI T1’s, using DAHDI version 2.6. I have both “tT” options set for both queue applications in the dial plan. I have been told by another Asterisk guru that these transfers are intended to be “blind” between queues, I have not tested it, but even if it works that would not fly by management. I don’t see anything in the logs other than a hang up when these failures occur. I have not been able to replicate the problem in testing with calling into the system with a cell phone to simulate our real callers.

Hopefully I’ve laid out my predicament pretty well. Does anyone have any brilliant ideas? Thanks in advance…