Yeah I had the exact same problem. Big hulking transformer with a linear reg. Rated at 12V 1000mA but kept getting the battery symbol and rebooting. And that was with only one drive too. Got mine from Dick Smith in Oz (kinda like Radio Shack but started by an Aussie)

Ended up finding some nice little switch mode jobs which besides being much smaller and lighter, they actually work. Only around A$20 for me too.

And anyway, you did follow the FAQ assuming the power supply could actually deliver it's rated power, then it should have been OK. Obviously it couldn't