I have several SPA504g deployed. We switched to DST last week and none of them will now keep the correct time. We reboot them and they are correct for a while, but then they "forget" to apply the DST rule and run 1 hour behind the current local time. I have attached the config from one of them (they are all identical). This is happening on the 7.5.2 and 7.5.5 firmware on two separate customer locations!
There is so many settings that's affect correct behavior. It include time offset supplied by DHCP during device startup, current device's date and time, date and time supplied by NTP server (if used) as well as following configuration values:
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