When I have everything in my room on (the 3 19" monitors, studio monitors, ssurround sound, computer, tv, and consoles) and when the power goes out I hear a huge sound like that also. It's like a pop and then sounds like the generators just got blown up in Tribes 2 :-D. I also hear a lotta cussing cuz I haven't bought a UPS yet and I'm always in the middle of something. So you're not alone.
-Donovan