Hi,
I have found the problem and it's exactly as described by der Reparatur in Winterthur; Bridge Diode blown and internal fuse-3,15A. I have found the replacement parts at Pusterla.
[link|https://derreparateur.ch/sonos/sonos-play-5-reparatur/|SONOS PLAY:5 Reparatur – Der Reparateur – Repariert Elektronik|new_window=true]
[link|https://derreparateur.ch/sonos/sonos-play-5-reparatur/|https://derreparateur.ch/sonos/sonos-play-5-reparatur/|new_window=true]
Something caused the fuse to blow (it was melted plastic) and one internal diode of the bridge is shorted. On the next link to youtube, the person describes that the 400v Elko caps were slightly swollen and replaced them too, plus a smaller 100Uf cap. He also recommends replacing all capacitors.
[link|https://www.youtube.com/watch?v=2R8hKdGTIgQ|https://www.youtube.com/watch?v=2R8hKdGTIgQ|new_window=true]
The problem with Sonos and many others is they run from Apps and the power supply is always energized. It will increase longevity if you unplug the device if not used regularly.
Repair cost by Sonos is 199.- in Switzerland.
[link|https://www.isonatec.ch/sonos-reparatur|https://www.isonatec.ch/sonos-reparatur|new_window=true]
To do this with damaging the circuit board Pads/Traces, I require a professional grade de-soldering station with vacuum solder removal. I have a simple soldering station and it cannot supply the energy required to melt the solder and the risk of lifting the very small pads is great.
Good luck,
Mark