I have an electrical problem and I’m trying to see if I can repair it myself, or do I need an electrician. In my family room, behind some large, hard to move, cabinets that house my AV system is a standard wall outlet with the usual pair of AC outlets. One outlet works and the other, it seems, does not. My house was built in 1993; all AC circuits are at least 15 amps; and all are grounded. Until this problem, I’ve had no electrical problems. Here is what I know: Connected to one outlet is an AC power strip, to which I’ve connected a TV set, BluRay player, and an AVR. The other outlet has a stereo power amplifier connected directly. The power amplifier cannot be switched on, but the other 3 items all work as usual. My first fear was that the stereo power amp failed. It’s a B&K EX4420, built sometime from 1993 to 1998. I bought it used in 2008, and until now, it's always worked well. Until I could not get it to power up, it showed no signs of trouble. However, my problem might be the AC power line and not the amp. Upstairs, directly above family room, is another pair of AC outlets in my bedroom. It has a similar problem, one outlet works and the other does not. They share the same wall as the outlets in the family room, and they might be on the same circuit. I can get to this one with a power outlet tester, like this. One outlet was CORRECT (2 green lights) and the other was OPEN HOT (no lights at all). I checked all the circuit breaker switches. They seem alright, none were tripped. What do I do next? If possible, I’d like to avoid pulling out the heavy B&K amp from it’s place in the cabinet. It’s a very awkward job, and I’d need help doing it.