I have a Polycom ip6000 phone that has been working on a sv9100 for over a year with no issues. The other day it stopped working with a failure to register. moving the Polycom to other Ethernet physical ports and it works on 2 out of the 3 ports so total it works on 2 out of 4. We also have another Polycom ip6000 that works in every port including the one in the conference room the original one stopped working in. I plugged the "bad" one directly into the switch and still it fails to register. No network changes have been done physical or program when this started. I have looked at the "bad" Polycom via the web interface and the programming has not changed and matches the good Polycom. To sum it up... I have a Polycom that previously worked on all network ports but now only on some, I have another Polycom that is programmed the exact same that works on all the ports even the ones the "bad" one does not work on. When plugged into the ports it does not work on I get a failure to register and cannot ping it or interface it via the web. I can move it to another port on the same switch and everything works perfect. The "good" Polycom works on all ports of any of the switches. Is this a bad phone? Ideas?