I also encountered this problem just the other day. Tried to unplug it, reset and even reloading the firmware from a usb stick (the old way).
Got it working for a day and then it started over again when I restarted them the next day.
Turns out I'm an idiot. I thought that the forever blinking light for bluetooth was because it wasn't correctly connected. I'd accidentally pushed the sound off button on the remote, the one with a symbol with the speaker and a cross, in the middle of the volume up and down.
Just telling to perhaps help other idiots like me , if the led is blinking you'll never get any sound cause it means you've turned the sound off.
