Trunking to Floating IP of HA Pair

Anyone run into any difficulty trunking to the floating IP of an HA pair? If I trunk to the boxes actual IP works fine. Calls complete in/out. If I trunk to the floating IP in/out calls fail.

Here’s an example:

Invite goes to (floating IP)
Response to the invite changes the contact URI to (IP of the node that is active)

This seems to screw the call up and it won’t complete. Does something special have to be set in the SIP or trunk settings in the FreePBX to make this happy?

Under the SIP settings section:

This added bindaddr= to the sip_general_additional.conf file

This has resolved the problem, invites are getting responses from the floating IP and calls are working now.