Polycom 650 now hangs when loading the SIP application via TFTP

Hello Polycom experts,

I'm stumped. I have 6 Polycom 650s (with sidecars) and 25 Polycom 330s that are configured via a tftp server on my network. This setup has worked fine for over a year.

Two days ago one of the 650 phones was restarted. It loaded the boot ROM and grabbed the config files from the TFTP server as usual. No problems with that. However, when it loaded the SIP application (we have version 2.2.2) it hung. I believe the message on the screen said something about processing configuration files. It also displayed the phone's MAC address and other network information.

So I rebooted the phone, did a firmware reset (i.e. holding down the 4, 6, 8, * at startup) and it loaded with the configuration files saved locally from the TFTP server at the last successful boot. At this point there was no TFTP server configured. Under this configuration the phone started up successfully.

What's strange about this is that the configuration files on the TFTP server have not changed for a long time. The files stored locally on the phone are identical to the ones server by the TFTP server. The only difference between the phone working and it not working is whether its configured to connect to a TFTP server.

To be sure, I put the default configuration files for firmware version 2.2.2 on the TFTP server and changed the phones cfg file to load those instead. When I rebooted the phone I configured it to use TFTP again. From the TFPT logs on the server, it appears that the phone read the updated cfg file and loaded the default configuration files. It also updated its log files on the TFPT server. Unfortunately, instead of working the phone loaded the SIP application then displayed a blank screen. I left it that way for 30 minutes to see if it was just taking longer to load than normal but it never finished loading.

So I did a firmware reset like before and the phone booted fine with the old config files, not the new ones that were supposedly saved in the previous step. So the phone basically works but I can no longer configure it. It's configuration is essentially frozen.

Can anyone suggest troubleshooting steps for fixing this? This will be a problem if I ever need to change the phone configuration.

Thanks,
Tim