The obvious is always a good place to start.
Yes, it is plugged into an operating outlet.
I talked to Scott this morning and he suggested checking for a shorted speaker wire. I am using banana connectors that don't appear to be shorting, but I will do a more thorough exam when I come back to town Monday.
I have Mirage FRx threes that are rated at 8-ohms. My "old" receiver is a Marantz 880 mkII and never had any problems like this.
My feeling is that trouble comes in 3's: I bought a stereo receiver off e-bay to drive my back yard speakers, it arrived dead, my video camera gave up the ghost, so I'm thinking that this is the third bit of trouble.
I should be good for awhile.