What's Wrong Everything's hooked up, but why is Gandalf's voice coming from the left surround speaker? And that supposedly "teeth-rattling" subwoofer (so said the sales guy) isn't even shaking the martini glass you put on top of it. Weird. By the way, why are you drinking in the middle of the afternoon?
The Problem You've probably just got your signals crossed. With all the audio wires in the back of A/V gear - speaker leads, RCA cables, and digital connectors - it's no wonder getting the speaker channels mixed up (and mistaking outputs for inputs) can happen even to the savviest custom installers. That midday martini probably didn't help, though.
The Cure Obvious Man says take the cables out of the wrong jacks and put them in the right ones. But his sidekick, Advice Lad, has a bonus tip: To make sure this doesn't happen every time you redecorate or switch apartments, stick some labels or masking tape on each wire and write on them what the wire is for. Feel free to color code the labels (the guys from Queer Eye would be proud!). Oh, and switch to Red Bull when you're setting up gear.
What's Wrong Your air conditioner kicks in, dimming the TV picture - possibly even tripping a circuit and causing a power outage. Pretty annoying, yeah, but downright gasket-blowing when it happens during the last five minutes of CSI.
The Problem The wall outlet cannae take the strain, Cap'n! It's probably because you're pushing it into the red zone by having a current-sucking appliance (air conditioners, vacuum cleaners, toasters, and refrigerators are the worst) plugged into the same outlet strip as your home theater gear. And those coronary-inducing outages could still happen if two separate outlets are on the same power circuit in your home.
The Cure Plug your major appliances into outlets that aren't on the same power circuit as your home theater. Duh.