Thank you for the clarification in your second post.
When tracks rapidly skip exclusively on a Chromecast group, it usually points to a breakdown in communication within the group itself. When Roon plays to a Chromecast group, it hands the audio stream over to the group’s “leader” device (which is assigned dynamically by the Google Home app). If any device in that group loses sync, experiences a brief network drop, or if the router struggles to handle the multicast traffic, the group stream collapses. Roon interprets this sudden stop as a signal to try the next track, leading to the rapid skipping behavior you are seeing.
Since individual playback works perfectly, we know Roon and your Mac Core are healthy. To get this group working again, please try the following steps:
Rebuild the Chromecast Group
Sometimes, the Google Home app’s internal routing for a group gets stale or corrupted.
Open the Google Home app on your phone.
Delete the existing speaker group.
Create a brand new group with the same devices.
Test a Smaller Group
If rebuilding the full group doesn’t work, try creating a smaller group (for example, just the two Nest Audios) to see if the issue is specific to mixing the KEFs and the Nest devices.
Router Settings
Chromecast groups rely heavily on multicast routing to stay in sync. Check your router’s administration settings and ensure a feature called IGMP Snooping is enabled.
If the skipping continues after you have recreated the group, please reproduce the issue and note the exact date, time, and track name when it happens.
Oddly, recreating the group with all speakers at the same time didn’t work. Nest only speakers worked; KEF only worked.
Then I created a new group with KEF + Nest, and that worked… One by one I added the rest of the speakers and now it’s working.
I couldn’t find IGMP Snooping in my TP-Link Deco mesh network app, but apparently it’s enabled by default. So it definitely looks like Google’s speaker group routing got borked.
Since rebuilding the group temporarily resolved the issue, it heavily points toward the TP-Link Deco mesh network occasionally dropping the multicast “sync” between the speakers.
While we wait for your timestamps tomorrow, there is one setting you might want to look at in your TP-Link Deco app: By default, the Deco system tries to seamlessly move wireless devices between network bands and mesh nodes to optimize speed.
If you go into your Deco app, select your wireless KEF and Nest speakers from the client list, and toggle “Mesh Technology” OFF for those specific devices.
Whenever you are ready, just drop the exact timestamp and track info here, and we will pull the diagnostics to see exactly what is happening under the hood!
I was able to find the Mesh setting when looking at the Nest clients, but for the KEF speakers, the setting wasn’t available.
So… since the KEF speakers are wired ethernet due to KEF’s infamously horrible Wi-Fi… I tried disconnecting the ethernet cable, reboot the speakers so they switch to Wi-Fi, and now the I can disable the Mesh setting in the Deco app.
It’s now working.
I hope that it continues working, and also that the Wi-Fi proves stable with the KEFs. I spent many months, and tried several routers, to get them stable. The Deco mesh system was the most reliable and easiest to setup, so hopefully the KEF Wi-Fi is ok with them as well.
Just circling back on this. Were you able to see how things performed over the weekend, and did you notice any changes in the issue we were discussing? Let us know what you found, and we can take it from there.
