[sorry about the fonts, colors, and formatting here. I cannot properly control the environment in this response for some reason]
Are you using the phones in a SPA9000 environment?
If so, perhaps there is a configuration problem.
Please verify that phones and SPA9000 are at the latest versions of firmware.
Please verify that all phones are on the same LAN and that your LAN environment is not distributed across switches which may be restricting proper communications between the SPA9000 and the phones. [example multicast may be restricted and cause incorrect SLA functionality]
Here's how the phone's icon and line key behave in a shared line appearance [SLA] environment:
SLA’s display different phone icons next to the line keys on multi-line phones with displays.
An inbound call causes all phones to ring. The SLA Line Key will flash red and the shared-line icon will become animated.
Any phone can pick up the call by going off-hook and pressing the flashing line key.
The connected phone will have a solid-red line key and the icon will change to double-headed arrowßèto indicate 2-way conversation.
Other phones’ Line key will flash red and their line icon will change to indicate that the line is busy
When the answering phone puts the call on hold, all the phones' icons change and their line key LEDs flash at a different speed indicating the call is on hold.
Any of the phones can press their flashing line key and speak with the caller.
For easier testing, only concentrate for now on the phones connected to the same switch as the SPA9000.
An easy test to determine if all is well on the LAN is to force the SPA9000 to reboot with http:///admin/reboot and then carefully watch the phones. Every phone must reboot when the SPA9000 reboots. If any phones don't reboot, that is an indication of multicast being inhibited on the LAN.
In order to eliminate configuration problems, consider configuring SLA on the phones using the SPA9000 setup Wizard.
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