T41S Common Area Phone not answering

[SpencerportCSD]

Are purchased Yealink Y41S phones for some common area phones in Skype for Business 2015 on premise. We login using Pin authentication. We can make calls out from the phone, however when we try to call the phone we get a message "is in another call". Traces from the phone show the call coming in but the phone itself is saying it is Busy.

Any ideas of what to look at.

[jolouis]

Is the phone set to Do Not Disturb?

This is our #1 response to service requests when callers say they can dial out but are not getting any calls in.

[SpencerportCSD]

The phone does not have a Do Not Disturb option now that it is a Common Area Phone. We have 3 phones setup this way for testing and are all having this issue. We have factory reset them and set them up again to be sure we were doing it correctly. The log file shows SIP/2.0 486 Busy Here even though no one is on it or even touching it.

[jeremie.greub@swatchgroup.com]

We have exactly the same issue with the T48S (SfB).

We see the exact same behavior.

We tested the user (sign-in with PIN code) with another phone (a Polycom) and it is working fine. The issue come from the Yealink phone itself.

Set as CAP : enabled
Firmware Version 66.9.0.45
Hardware Version 65.0.0.2.0.0.0

Maybe, the firmware is the issue...

Any help please?

[SpencerportCSD]

We downgraded the phone to firmware Version 66.9.0.25 and then the phone started to answer.

Yealink support indicated that developers were looking into it.

On a related problem we have been having tons of issues with getting the Yealink phones to allow pin authentication.