P3 connected loads blown fuses

Very strange failure this AM.

Powered up my amps this AM and had a good listening session for an hour or so.

Total up time on the connected loads with warmup was a little over 3 hours.

Left everything on to break for breakfast, came back and everything connected to the P3 was dark.

The P3 was still on line, just no load.

Lost the following fuses;

Rives PARC / 1 - 500 mA slow blow ( fortunately only 1 of 2 PARCS was powered in use )

Pair of Atma Sphere M60 MkIII / 4 - 3 amp slow blow ( 1 - output B+ and 1 - output filament fuse in each amp )

The PARC is always on and draws about 6 watts.

Each M60 ( when on ) draws about 95 watts.

Total connected load when listening is less than 200 watts.

All 3 loads are connected to different zones, A, B and C.

Pulled the affected gear and ran some tests, no issues found.

Replaced the fuses and everything is back on line.

I had the network disconnected so I can not check the log, I tried to connect anyway but the powerplay page is down.

Very odd event.