Firmware Upgrade breaks SNTP

[Mark1972]

We have 10 phones (9 - T26, 1 - T28) and a 3CX PBX server. The phones get their provisioning from the server for SNTP. SNTP working great.

We upgraded to the 3CX supported firmware 6.70.0.103 and SNTP stops working on 9 of the 10 phones. Why?

I've tried the following:

1. Reset to factory default and reprovision - SNTP does not work.

2. Manually set SNTP on the web interface - SNTP does not work.

3. Manually set SNTP on the phone's interface - SNTP does not work.

4. Downgraded firmware back to 6.61.0.83 - SNTP does not work

5. Upgraded firmware back to 6.70.0.103 - SNTO does not work.

Again 1 of the 10 phones is working great. It's not a firewall issue since everything was working prior to the firmware upgrade and 1 of the phones gets its date/time correctly.

Any thoughts?