(10-27-2017 09:50 AM)siny Wrote: Asterisk 15.0, Yealink firmware 82, still the same problem.
This looks like "not willing to fix"!
Seems that other phone manufacturers know something more?
PLEASE Yealink, fix this, because that's the only reason I don't recoment your phones to everyone...
For people who follow this thread in future, I have done a whole bunch or research, and it appears that Yealink are actually doing nothing especially wrong
But nor is asterisk.
1) The XML Notify message being sent does not have an obvious value for "cannot call" available to it in the RFC. It can only really indicate call states, and uncallable is the same as not-on-a-call.
2) The "Subscription-State" header is nothing to do with this issue (except as a way to make the button red), it simply indicates that the handset has an active subscription for the BLF line in question. Subscription-State: terminated indicates that the BLF subscription is no longer active so no state will be sent.
3) If someone can demonstrate this working as we all want it to on a different handset type, and grab a trace of the packets sent, I would be VERY interested in the difference. What I think you might find is that they use an alternative XML standard for the NOTIFY, which does not handle call-state properly