I have been using 2 Play 5’s (gen 1) as a stereo pair for a couple of years without problem. The other day, one speaker seemed to ‘disappear’ from the system. I have tried a set-up, both through the app and via an ethernet cable and router, but with no joy. One speaker still works fine, but the one that ‘disappeared’ doesn’t. On the top, the button that looks like a speaker with a forward slash through it is constantly flashing….Help please|