Possibly either a temporary power surge or that any of the power tubes are or are going bad.
I'd suggest a call to Dared and tell them what happened. No sense replacing that expensive 845 if it was just a house power glitch, and even pulling a tube to test it may violate a warranty.
I'd suggest a call to Dared and tell them what happened. No sense replacing that expensive 845 if it was just a house power glitch, and even pulling a tube to test it may violate a warranty.