for what it’s worth I am having the exact same nightmare. Not sure exactly
when it started but I believe it was a change in 220.127.116.11 / 18.104.22.168-rc1 (I am
running 1.8.9rc1). I also have Polycom (335, 550, 650) and blind transfers
are broken. All legs of the call are dropped when the xfer is executed. A
calls B, B xfer to C and (C) blips for a split second like its ringing but
then all calls go dead. I tried to debug myself using some sip tracing but
I didn’t get very far. I even tried mucking around with a few settings in
my Polycom provisioning I thought might be related e.g.
and also upgraded to the new 3.3.4 firmware which is out yesterday, didn’t
change a thing.
stuck here for now, Attended xfers seem to work. I am not sure this is a
Polycom-specific issue because I was seeing this bad behavior even using
some Softphones I set up for testing.
my next recourse is to try rolling back to 22.214.171.124 or earlier and if that
fixes it then I will open a JIRA ticket with more details.