What went bang, smelled of "I'm fried", yet left it in working order...???

Hi gang - wasn't sure if this should go here under amps or tech talk, but here goes: normally, I'd call the salesman I work with at my LAD, but they're closed Sun. & Mon. and I'm loosing sleep over this as I feel I'm on very thin ice.

My wife and I were watching a movie late last night, and after the movie we were sitting on the coach discussing it when we both jumped when we heard a loud bang coming from the media console and smelled an electrical burn. Sitting on top of the console is a Dan D'Agostino Progression Stereo power amp, a McIntosh C53 preamp, and mounted directly behind this on the wall, a Panasonic plasma TV.

Nothing tripped a fuse, the TV was still on, both sets of power meters on both the Dan & Mac were still lit. I streamed a test track that has a lot of bass that when I turn up to a certain volume, has the Dan's power meters hang at 400 watts for a few seconds, and they did - just like always. Everything seems to look and sound fine.

So, while I'm not asking for anyone to try and guess which of those three components made the bang, what I am asking is for any of you here who have an electronics background tell me what electronic part (in either the preamp, amp or TV) possibly could have made a loud bang releasing an electrical burn smell, yet "seemingly" leave everything still functioning as normal...?

--thanks and cheers!