Sonos time update every second ?!

What are you observing that indicates this behaviour?

Why do my Sonos products constantly try to update their time EVERY single second.Because time itself updates every second?

Why do my Sonos products constantly try to update their time EVERY single second.Because time itself updates every second? I'm not sure you understand what NTP does. However it's a funny answer 😃

You are correct on both counts. 🙂

NTP (Network time protocol) is used to sync systems time from an accurate source. Typically done every hour or so to check for the millisecond time slips. Sonos does this every second if not less on every device on your network. It's stupidly noisy.

I've just run a quick Wireshark capture for NTP traffic on my network, which has 10+ Sonos devices. I'm not seeing any unusual or excessive NTP traffic. Is it possible that your Sonos devices are unable to reach their specified NTP server?

How do you know? Are you sniffing traffic through your internet gateway? There is other traffic, internal to the LAN, every second. For example STP BPDUs are sent once per second. And (I believe) sync timestamps are exchanged every second in a playing group.

Why does this matter?

I've just run a quick Wireshark capture for NTP traffic on my network, which has 10+ Sonos devices. I'm not seeing any unusual or excessive NTP traffic. Is it possible that your Sonos devices are unable to reach their specified NTP server? They can access the local LAN NTP server perfectly and do so every second. I can understand a sync between speakers in a group. To me it seems very strange they need to speak out to the world every second. Looks more like data being sent out my network to me. I'll have a look at the packets and see what's being sent and confirm it's actually an NTP request packet.

Does your wireshark see the whole LAN then ? You'd need a mirror port or a HUB to see anything other than on your leg of the swtichport otherwise.

Does your wireshark see the whole LAN then? You'd need a mirror port or a HUB to see anything other than on your leg of the swtichport otherwise.
No, you're right ... I'm not seeing the relevant NTP traffic.

Why do my Sonos products constantly try to update their time EVERY single second.Because time itself updates every second?

Future history books will refer to this exact moment as the beginning of The Great Correction. :8

Running packet capture on my firewall and I wasn't seeing any Sonos related ntp packets so I power-cycled a ZP and got one.

18:40:20.415504 IP SonosZP80-AC.home.32774 > tick.no-such-agency.net.ntp: UDP, length 48
18:40:20.444057 IP tick.no-such-agency.net.ntp > SonosZP80-AC.home.32774: UDP, length 48

Last look Sonos was using [0|1|2|3].sonostime.pool.ntp.org for this not the above resolved name.

If ntp is getting good time responses it shouldn't be doing many checks, when it fails it should initially do more but back off to a less intrusive level after several failures.

You can play with ntp date as root or sudo, -4 means use IPv4 and you can use 0 to 3 for the first bit:

ntpdate -4 3.sonostime.pool.ntp.org

You should see a response like this:

2 Apr 19:27:26 ntpdate[4157]: adjust time server 162.210.111.4 offset 0.003380 sec