scenario: 20 amp ckt. with 4 receptacle outlets on the ckt. Power strip plugged in with three lamps,a computer,clock plugged into one receptacle. Coffeemaker plugged into another outlet and the other two aren't being used. With the coffeemaker on the two lamps flicker intermittently,with the coffeemaker off, lights still flicker,what gives? Circuit is drawing about 14 amps with everything on,and you can hear a very slight crackle at the very old 20 amp breaker. I'm bewildered,any troubleshooting wizards out there.