Hi everyone,
I'm hoping someone has seen this before because we've reached the point where we've exhausted most of the obvious troubleshooting.
This is a commercial installation at a shop.
System:
- 4 x Era 100
- Sonos S2
- All speakers on the latest firmware
- All on the same WiFi network
- Cisco Meraki enterprise WiFi
- Same VLAN
- Same subnet
- Same AP
The issue:
Every speaker works perfectly on its own.
Any combination of 2 speakers will group and play correctly.
As soon as I add a third speaker to the group, the Sonos app shows all speakers grouped and playing, but only the first two actually output audio. The speaker added last is always silent.
I've now installed a fourth speaker and the behaviour is identical. I can only ever get audio from two grouped speakers, regardless of which speakers I choose.
Another symptom is that when the system is in this failed state, the two speakers that are playing will occasionally stutter or briefly stop and start.
Things we've already checked:
- Factory reset all speakers.
- Set the system up from scratch.
- Confirmed all speakers are on the latest firmware.
- Tried multiple music sources (Spotify and internet radio).
- All speakers are connected to the same AP, VLAN and subnet.
- All speakers are discovered correctly and respond immediately in the app.
Our network engineer has also spent a considerable amount of time investigating the network.
He has confirmed:
- Bridge Mode.
- Bonjour.
- No client isolation.
- IGMP snooping enabled.
- Added an IGMP querier as a test.
- Multiple packet captures showing clean multicast behaviour.
- No multicast drops.
- No missing SSDP responses.
- No stale multicast memberships.
- Speakers are discovering each other correctly.
He also confirmed that we have multiple other branches running Sonos on the same Meraki configuration, including sites with three or more speakers, without this issue.
At this stage we're unsure whether this is a Sonos software issue or whether there's something unique about this installation.
Has anyone seen behaviour like this before?
