Hi,
I hope to find help here, because after hours of troubleshooting I’m completely lost. 
Since 3 days all of my speakers disconnected from the Wifi. All at the exact same time. Since then, none of the speakers were able to reconnect. While digging into the root cause of the issue, I’ve recognized, that the speakers send DHCP Discover messages and the DHCP server replies with DHCP Offer messages. After the DHCP Offer, there is never a DHCP Request message from the speakers. I’ve dumped the traffic on the DHCP Server and on the access point (Unifi U6-Lite). The packets were seen on both ends. Although I don’t see any RX/TX drops, I can’t confirm that the DHCP Offer ever reached the speaker.
The weird thing is, based on the Unifi Controller information, all speakers are assigned to the correct reserved DHCP addresses, but none of the speakers is reachable.
I’ve gone through countless troubleshooting hints within the community and Google searches, i.e.
which describes pretty much my issue. However, my DHCP server sends two kinds of offers:
- Broadcast (ff:ff:ff:ff:ff:ff)
- Subnet Broadcast (i.e. 192.168.0.255 (/24)
(in this order). There is no DHCP offer sent as unicast.
In despair of the situation I’ve connected on speaker (Play:1) wired to the network. This didn’t change anything, although I’ve learned, that after connecting a single speaker in the network turns on Sonosnet. 
This led to all speakers move to the APIPA address space. They were able to communicate to each other, but to nothing else - naturally. However, after assigning my client an APIPA address I was able to access
http://<PLAYER-IP>:1400/support/reviewUnfortunately this wasn’t really helpful - at least for me. No logs, no obvious errors, but still
contents of /proc/ath_rincon/status
Debug info for INFRA mode at 9275
Mode: INFRA (sonosnet)
Operating on channel 2437
Home channel is 2437
RF Chains: RX:2 TX:2
RF Chainmask: RX:0x03 TX:0x03
Max Spatial Streams: RX:2 TX:2
Noise Floor: -100 dBm (chain 0 ctl)
Noise Floor: -100 dBm (chain 1 ctl)
Noise Floor: -100 dBm (chain 2 ctl)
PHY errors since last reading/reset: 4038717
OFDM ANI level: 5
Ch11 Spur Immunity Level: 0
HAL Reset Failures: cnt: 0 last: 0
Region: 2The PHY errors seem to be interesting, but I can’t figure out, what they mean.
After something between 1 and 2 hours it seems, that all wireless speakers left the Sonosnet and reconnected to my Wifi. After some time the Unifi Controller showed the correct IP address (DHCP reservation), but still not reachable.
I’m completely out of ideas how to proceed. I’m using multiple Play1, SYMFONISK and a Beam. They were running for years and I’ve never experienced an issue like that, out of nothing. There were no network or configuration change. I’ve recognized the issue after getting up in the morning.
Based on previous experiences with the (sometimes) mediocre quality of the Unifi firmware, I’m not sure whether the Unifi devices suddenly drop the packets. I’ve seen a similar behavior with the access points (especially for MDNS), but never with the Unifi switch - that’s the reason why I’ve connected a single speaker wired.
As I’m not sure if this could be related to the specific SONOS software version, I’ve added the exact version, gathered through the support review, to the title. Even if it’s related, I’m not sure how I should now be able to update the speakers, without giving them access to the internet… 
Hope that someone got an idea. Otherwise I will try to get in touch with the support, although I’m afraid that they will ask me to restart my router, reset Wifi, re-paint my walls and whatever they find in their consumer KB.
Thanks for any ideas.
