Yealink T28 not releasing call on blind transfer

[turnstonelimited]

Running 3CX v11.0.28976.849
Yealink SIP-T28P 9.70.0.103 (3CX supported firmware version)

This is what happens currently:
A calls B
B blind transfers to C (using method: TRAN->extn->TRAN)
B does not release the leg of the call until C answers (the display on the phone shows the call has left, however 3CX still has a leg open to phone B until A and C are connected)

This is what I would like to happen:
A calls B
B blind transfers to C (using method: TRAN->extn->TRAN)
B releases the leg of the call when TRAN is pressed a second time

On the Yealink phone, under Phone->Features->Transfer Settings
I have semi-attended transfer disabled
Blind transfer on hook enabled
(however i have tried all possible combinations of the transfer settings attempting to get this sorted)

any help would be appreciated.
i will upload 3cx config and yealink config files at a later stage if necessary.

 

[jj1]

Hi,

We have exactly the same issue with Yealink Phones and 3CX Call Queues. As an example the Yealink T46GN is not releasing call on blind transfer until answered/timed out at the other extension and this seriously delays new queue calls from reaching the Agent (20-30 seconds sitting idle)

The behaviour only seems to occur with Yealink phones, I have tested using a Snom 870 and the 3CX SoftPhone which release the call straight away and the next call queue can come straight to the Agent.

I have posted on the Yealink forum under an existing thread so please can you add to that and this thread if you are having the same issue.

[T21P] Problem with Blind Transfer - http://forum.yealink.com/forum/showthread.php?tid=4170&pid=16614#pid16614

 

[jj1]

Yealink have been really helpful in regard to this strange behaviour and after sending some traces from Snom and Yealink phone they have now released a new T46G Firmware (28.80.0.72.rom) that changes the blind transfer behaviour to match what we see with the Snom phones.

We've tested with only one agent logged into the call queue and as soon as we blind transfer the first call the second call comes straight in now.

Great job Yealink

For other Yealink models you may need to contact Yealink support and request the appropriate firmware, I think they will include this in the next major release cycle anyway.