When using the Headset on a 79XX Phone, the Phone also enables the Handset for some Reason.
If you pick up the Handset the Microphone gets active.
When you hang up the Handset only the Microphone gets deactivated.
But if you have set the Handset Volume to Maximum you still can hear the Caller on the Handset while using the Headset.
I've tried different Phones (79X2 and 79X5), different Firmware (9.0.X), different CUCM (7.X and 8.X) and could reproduce this Issue.
Is this a Issue which could be triggered by faulty Software or is the Phone designed to work like that?
(Maybe it's just bridging the Handset and Headset Ports)
I've found an old bug with Firmware 8 which was junked:
However it is a Issue for a Customer of ours...
Thanks for any Help.
This is a hardware "feature" built into these phones. The handset speaker button is active, however the microphone is inactive. This cannot be disabled by any software feature.
The reason for this is in environments where you may have a agent using their headset and a manager or supervisor may want to come over to pick up the handset and listen.
Hope this answers your question!