There are a few reasons this could happen. One of them is a hardware failure. The WIFI card could have gone bad and thats why it cannot connect wirelessly to your network.
Another reason could be it needs a software update. I just did a firmware update today that I did not get a prompt for. While it is connected via ethernet, check for an update. Apply it if one is available.
Another reason is because of an update that was pushed out to your router, but I feel it is a problem with the Playbar.
I don`t get it. A working setup just stopped working, because an update is available? Sorry, but that does not compute.
What did Sonos Support say about your issue?
