[W52P] SIP CANCEL with "Call completed elsewhere" shows missed call

Hi all,

I am running Asterisk 13.6 on FreeBSD using PJSIP. I have two Yealink W52H handsets on a W52P base and one Polycom SoundPoint IP 450.

I have an extension set to ring all three phones when dialed. When I dial that extension and I pick up any of the phones, the Polycom phone shows no missed call (as it should); however, both Yealink handsets log a missed call, but that shouldn't happen.

I verified using network traces that Asterisk did send the correct Reason: header with its CANCEL message, as shown below:

CANCEL sip:livingroom@10.88.5.6:5062;transport=TCP SIP/2.0
Via: SIP/2.0/TCP 10.88.5.18:47894;rport;branch=z9hG4bKPjowr7UKfrONlOZR83eWjkaiTPRtHLSAIo;alias
From: "Poste salon" <sip:4012@10.88.5.18>;tag=1XpNz2Ds--8dngCB9eQneaOh7SAbWJzu
To: <sip:livingroom@10.88.5.6>
Call-ID: y.1DPWeUhfhN8ElX.u1zy77B.3Cz3jBr
CSeq: 16926 CANCEL
Reason: Q.850;cause=26
Reason: SIP;cause=200;text="Call completed elsewhere"
Max-Forwards: 70
User-Agent: Asterisk PBX 13.6.0
Content-Length: 0


I believe this is a bug, since I expected no missed call to be logged on the Yealink headsets, yet they do.

The Yealink W52P base is running firmware version 25.73.0.40. Both handsets are running firmware version 26.73.0.11. I can provide config.bin, syslog (level 6) logs and pcap traces on request.

Regards,
x0r