Do you have "all" both in read/write in /etc/asterisk/manager.conf ?
It seems like there are missing manager events in your setup. Also, be sure to set in sip.conf
callevents=yes
If you can reproduce the issue with those two settings, then I will have to look at a detailed capture of manager events on your server to trace the issue. I am almost sure it is not a fop2 bug but some problem with manager events. handling multiple calls is something every user does and they do not experience the issue you describe. So be sure to set callevents=yes in sip.conf and that your manager.conf is not filtering events at all.
In any case, you can try to catch me on the live help. Best regards,
