99 Malibu 3.1L electrical problems

The other day I noticed that my lights would dim when I stepped on the brakes, and the radio (aftermarket Clarion) would turn off. It would come back on when I took my foot off the brake. Then the car started to die when I stepped on the brake. Now, after it dies or you turn the car off, it won't start again and the lights & warning lights won't come on, or are very dim. If you wait a few hours or over night, it will start. Could the brake light switch cause all of this, or should I look elsewhere? Maybe the ignition switch? :banghead::confused:

My first thought is what is the output voltage of the alternator? It is entirely possible for the alternator to stop charging and not turn on the "battery" light.

I went to Autozone and had them check the charging system. He said it was charging fine.