I'm not sure what happened, as nothing was moving at the time.
I was trying to figure out how to get the Mach wizard to do an outside to inside facing cut, when I heard something starting to crackle.

The only thing I can think of, was I fixed the coolant earlier, and at one point I rattled the back of the casing quite hard when trying to get the locline back together, so I wonder if I dislodged something, but the only obvious damage is the toiroid. Fuses are 6.3A anti-surge.