I have been experiencing static coming from the speakers when I operate both my CD player and stereo (AM & FM).

I believe the problem occurred shortly after depressing the brake pedal as I was approaching a stop sign. Soon after that, I noticed that I had to raise the volume to be able to hear the radio. Static began to be audible.

Anyone have any suggestions on what might be causing the problem?

It seems like you have bad contact in wires around the radio or cd player. Because when you apply brakes I think radio or CD unit moves, and some connections became lose. Try to check them.

Make sure the unit is grounded.