It sounds like having multiple Sonos devices wired (the Playbar and another) is creating a broadcast storm which is taking down your network. You can get around this by wiring multiple Sonos devices to a switch, then the switch back to one Ethernet port on the router.

If you already have one wired Sonos device, the others should be using SonosNet. Within About My System, check each device shows as WM:0

Just to clarify…

These other 3 speakers, are they Sub/surrounds or are they separate rooms in the Sonos app?

If they are either Sub/surrounds, only wire the Playbar as it uses it’s 5GHz radio to communicate with Sub/surrounds so they don’t need to be wired.

The picture above shows my internet situation, i have the ethernet connected sonos wired to one switch

the sonos play 1, play 5 and play 3 are all in seperate rooms.

i just tested, when i disconnect the sonos play 3 there are no problems with the playbar connected to ethernet

Looks like the router being used as a switch is the problem. You could replace that with a simple switch if you wanted to still wire the Play:3

I just replace the router for the switch and now i don't have connection problems anymore. thanks for your help. i am very interested why the router caused this problem because the router is functioning perfectly.

I switched to Rogers using the XB8 reconnected the basement Beam into my network using Ethernet.  That caused my WiFi to die.  After literally hours of connection attempts with WiFi only I disconnected the basement Beam and connected the main floor Playbar with Ethernet.

After re-connecting the Play:3 to the network using the reset and connect method through Network settings in the app I was able to play musing on all three devices using the SONOS net.  I had to exit the app to get it to acknowledge the change.  The app not terminating the connection dialogue.