Cisco has not claimed support for any Door Phones so far since we have not tested it. Howeve if the door phone follows local standard then it should theretically work with the UC320. Are you configuring it as a hot phone? If you have not done so, please do that.
I would recommend that you open simulatneously cases with both Viking and Cisco SBSC. SBSC is going to need logs and audio catpures to analyze why this failure is occuring.
It hooks right up to the FXS port and can be programmed to dial an extension (a blast group in our case).
There another Viking box that you can pair with this (don't have the part number handy) so that the people who recieve the call and press a button to unlock an electric door strike (we have this at this particular customer site -- it works very well).
I have installed the CyberData range of VoIP intercoms for Door Entry, with registration to Cisco Call manager, as far as I am aware Cisco have certified the product. Infact they also feature embedded Cisco features such as Cisco SRST.
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