H340 Not Powering On

This evening we had a power outage; I shut the H340 down cleanly (it and my others systems / router / modem) are on UPSes.

After the power returned it will not power up Image may be NSFW.
Clik here to view.

Symptoms are a Blue light is on at the top left hand front (power switch) but no other lights.

Pressing the switch will eventually power off the unit.

I have heard some fans run at one point while holding the switch down.

Any advice as to what I could (or should) try?

Still running WHS V1.

Peter