I have one of these VoIP boxes and it refuses to see any NTP servers. The ‘last sync’ time shows as 2016. Does anyone else have one ?
I have tried it with my ISP’s NTP servers and now with my own Firebrick router, which should be an NTP server too. I also tried setting the time on it by hand to the correct current value, just in case it was some stupidity where it might refuse to do the right thing if the difference is too large, as that is a bug that I have seen in the past with certain NTP clients.