I'm having the same problem. I have a UC540 with 8.6.2. I have a 7962G. On the phone itself, if I go to menu, device configuration, media configuration it says that Headset Hookswitch Control is disabled with no option to enable it.
Looking at some very old posts, it looks like you used to have to use CLI to enable this feature. Is that still true?
It there any way to get this feature working in CCA?
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