I have recently added a custoemr provided VVX 300 and a Soundstation IP 6000 to a version 15 3cx system. I configured them useing the "simple setup" using server IP address, user name and passowrd. These phones are off site. They register and we are able to dila out. When one phone calls another or if we call it directly thru did numbers, they ring but there is no "ring back" heard from the calling phone and it cannot be answered from either the handset, speaker or answer button. I do noth think it is firmware and both phones act the same and they are two different phone types.
welcome to the Polycom Community.
The Firmware question still stands as this is the minimum information you should provide for every post.
The community's VoIP FAQ contains this post here:
Jan 19, 2012 Question: How to troubleshoot Polycom VoIP related Issues?
Resolution: Please check => here <=
The above can be used to troubleshoot this kind of issues.
The next step after this, if you cannot find help via other community members and/or the community search functionality, would be a support ticket.
In order to raise a support ticket you need to work with your Polycom reseller as they need to do this for you.
If this is some sort of an Internet discounter please post either your phone's MAC address or your Polycom devices serial so I can look up who would be able to support you.
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
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