We are experiencing the same issue with answering or hanging up using the headset. We do hear the ringing on our side.
Interestingly, on Yealink's website, the 3CX logo appears on the WH64 product page, and we also received a promotional email where the 3CX logo is featured alongside the WH64.
For comparison:
The Yealink WH62 and WH63 headsets work perfectly fine with the 3CX Phone.
The WH64 works flawlessly with Microsoft Teams.
Here is a summary of the tests we performed:
Test performed on 3CX Windows Softphone V20, version 20.0.664.0.
I connected the WH64 headset. I confirmed that it is up to date. I confirmed that 3CX is up to date. I changed the headset in 3CX to the WH64 in: Micro, Speaker, Ringer. I selected the WH64 in the headset settings.
I performed call tests, tried to answer without success. I tried to hang up without success.
I restarted 3CX and repeated the tests, still without success.
I ran a test on Teams and was able to answer without any issues.
I tested with my WH63 and it worked immediately.
https://www.yealink.com/en/product-detail/headset-wh64
