My Polycom VX310 Deskphone randomly becomes unregistered. The network is not down; I hear phones ring and others are on phone calls near me. Everything is connected according the to troubleshooting guide.
All users were notified in the ANNOUNCEMENTs tab of this forum and via email - there is a system update rolling through the RC network beginning 01-09-2017 -- your issue could be related to the update.
There are several things that can cause phones to unregister randomly. Usually, it is related to the local network configuration or physical connection. I have seen things as simple as bad Ethernet cables, or loose connection, or bad switch ports cause these type of issue.
I have also seen things like load balancing, SIP ALG, DNS issues, switch issues cause these kinds of problem.
My best suggestion for you would be to call tech support and open an official case with us so that we can do some troubleshooting, make sure that all the provisioning in the phone is correct, and then help in any way we can to try and point you in the right direction if the issue looks to be related to a local network or connectivity issue.