Are these phones the same model and using the same protocol sip vs sccp as others that are working?
If you browse to the IP address of the phone and look at the time zone does it properly show it?
All same type 7821 using SIP.
A few phones show time one hour wrong and same when I browse to them! :( Time is wrong but timezone is correct.
Are they on the same firmware?
I have seen this issue caused by firmware not upgraded properly. If you browse to the network settings page do you see all parameters correctly, i.e. proper CUCM servers the phones communicate with, etc?
They were. Due to getting XML Parse Error TAC have provided a new firmware which we've applied to 'select' phones. This time issue was happening beforehand when all phones has same firmware. Network settings look correct.
I'm not convinced with these 78xx phones :(
We applied the very latest firmware which seems to have resolved the XML Parse issue but no fix for the time issue yet!
Please vote if it helps :)
Are all the phones registered to the same subscriber? I had this issue before, I SSHd into the subscriber and did "utils ntp status" and NTP was unsynchronized, apparently after a power outage.
NTP status looks good. This happens for a few phones on same CUCM. If I browse to the phone it shows incorrect timezone for affected phones but I they are all configured the same.
Before we jump to firmwares, just wanted to ask whether or not your date time group for that device pool is the correct one. Also, any chance whatsoever that your cluster DST file is not up to date (probably unlikely this late into autumn, but it's feasible)?
Same issue here, I am so pissed with the Cisco New SIP series.
I have the IBM J9 uploaded in TFTP, have the firmware upgrade.
The Phone shows in correct Timezone but the display time actually is GMT. But for me only one phone have this issue.
Got it solved at my customers. A keypad factory reset made it.
Unplug the phone, press and hold # and plugin. After 2-3seconds press 123456789*0#. That's it.