I have had a Soundbar300, Base Module 500 and the two little bose surround sound speaker working fine for a couple of years (here in NZ).
2 days ago the bar stopped connecting to wifi and wouldn't work with the tv. I did the factory reset and pulled the cord out, I can't get it to connect to the wifi again. I can connect it with ethernet and it will work through the tv, but then I cant add the other speakers to connect to it.
Sorry to hear that's happened - have you recently change WiFi providers? Are you trying to connect to a new router?
Also, when you mention a factory reset, did you follow the exact steps below:
If you've tried that, let me know and we'll discuss appropriate steps from there.