Help? Why Classe CAM-350s going into protection mo

What I thought would be an audio dream has turned into an audio nightmare.

I finally was able to purchase a pair of Revel Studios this past Sunday. The System:

Meridian 508.24 cd player
ARC Ref 2 Mk II preamplifier
Classe CAM-350 monoblocks
Revel Studios

I have the Meridian connected to the ARC via some Synergistic Research balanced, the ARC to the Classes via some generic Radio Shack single-ended and the Classes to the Revels via Kimber Bi-Focal XL cables.

The reason for the Rat Shack cable is that my previous speakers were just run-of-the-mill Klipsch bookshelf 2-ways. I lived in NYC for 11 years and couldn't really justify good speakers in my small apartment. I've slowly accumulated the pieces over the years with the Studios the last piece of the puzzle.

More background: I moved to Chicago a year ago during which time the Classes were boxed. They had not been used until Sunday (almost 13 months). I'm living in an 8 unit condo with 5 units occupied.

The Problem: After times ranging from 3 minutes to an hour, the speakers emit a short "zzz" (maybe one second long) then a "pop" then BOTH amps go into protection mode (flashing green light). I unplug the amps and take a look at the fuses. They look OK to me, but I guess I'm not sure what a blown fuse would look like. After waiting 30 minutes, I plug the amps back in, turn them on and start listening again. Two more times the same thing happened after various lengths of listening time.

Despite the Studios having a low 87 db sensitivity, the speakers sound loud and my volume is not going past 8 o'clock (this could be a related issue). Only during softer passages have I gone to 10 o'clock. In fact, as I did with the Klipschs, I used Rothwell attenuators to lower the noise floor (I hate hiss). This never was a problem with the Klipschs. The Classes "blew up" once with the attenuators and the Studios so I thought that might have been the cause, but the same problem occurred after the attenuators were removed.

Explanations?: I'm no expert so some of these suggestions might be outright dumb. Is it the Radio Shack interconnect? Both runs are either 6 or 8 feet (can't remember). Could there be a short? It's very odd that BOTH amps are experiencing the same problem which would imply shorts in both wires.

Is there a problem with the preamp? The ASC wasn't used for 13 months either. Before reinserting the tubes, I had them checked out by an ARC dealer who pronounced them fine.

Could there be an issue with my unit or building? For example, when the fridge sets in or turns off, is there some sort of "surge" causing the amps to go into protection mode? Is someone in another unit using some sort of appliance that could cause a "surge"?

To be so close and so far to audio nirvana has really upset me. As the amps are extremely heavy, I'd rather not have to box and ship them back to Classe. The again, they might not be at fault. I'm hoping some of you guys might have experienced this before and can recommend a simple and straightforward solution.

Thanks.

Andy