T43Us going "No Service" after reboot

[jonschwab]

We have encountered an issue with the T43U phones in one of our large HPBX/Metaswitch deployments. About 4 weeks ago, we go a call form our customer complaining that they were having reports of "No Service" showing on their phones. We can recover the phones by re-opening the MAC authentication on our Metaswitch and it will re-register just fine during reboots for about half an hour. Once its rebooted after that "No Service"

When we log into the phone GUI the information for the Username And Password we provide for the SIP Registration is gone. We also noticed the SIP-PS no longer has the token appended to it that was there initially when it downloaded its config from our SIP-PS.

We are now on the latest code .90 which we thought fixed the issue, but we got reports this morning that it is still occuring on the latest firmware.

We use an ADTRAN NID that connects to their network in order to provide a test point in the event of issues like this, the customer claims it happens right off the NID as well.

We are running out of Ideas on how to fix this headache, and was wondering if anyone out there has encountered this issue with the T43Us the Internet and forums so far have not provided us with any good solutions or explanation and submitting a bug report to Yealink has fallen on deaf ears.

Thank you in advance.