Re: Microsoft Roundtable and Nortel BCM50 - no dial tone
welcome to the Polycom Community.
The Polycom CX5000 telephony functionality is for an analog line only.
I can only assume that the PABX you are using is either digital proprietary Nortel or IP based.
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
Polycom Global Services
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