Can DC power surges cause fires?

My Audio Research D130 (which I was trying to sell- I cancelled it- LOL) caught fire last night. Flames, smoke, the whole nine yards. About a minute later, there was an audible sizzle from a new Jeff Rowland Model 102 power amp as well. This is the FOURTH time the left channel has blown on one of my amplifiers (the AR was recently refurbished after the protection circuitry failed, and an Aragon 2004 MkII is out for repairs with a failed left channel. It was the left channel on the AR that burned last night, and the left channel on the Rowland that sizzled. I thought it may have been a problem with my AC line, but everything else on those lines (which all run via a surge protector) is fine- some fragile stuff like a modem, wireless router, TV, old receiver and CD player. It's like everything that gets hooked up to the preamp- a 12 year old N.E.W. P-3- fries the left channel.

It's strange- I used a voltmeter to look for DC surges just a couple of weeks ago, and both amps and the preamp tested clean....I guess I need to know if DC surges can be cumulative, with the energy getting stored in the resistors and capacitors in the power amps, and after reaching a critical mass, the power amps implode (or, apparently, catch stinking fire- LOL).

Anyone else familiar with problems of this type. A friend of mine who's quite knowledgable says it's definitely bad capacitors on the preamp causing a DC surge into the power amps. Any of you people have any ideas? I just cooked $4000 of amplification last night, and I'm pretty annoyed- any help would be appreciated. All items were shipped out for repair today, including the preamp, although there's nothing obviously wrong with it.

Thanks in advance for any ideas/thoughts.