brakes messed up?
 

So i was driving today and when i step on the brakes the speedometer would drop to 0 and back to the speed i was going but the car wouldn't slow down. the speedometer just dropped to 0 and back to the speed. Also as the speedometer did that, the radio would turn off and back on. whats going on?

Sounds like a short somewhere in the electrical system. I think the reason the brakes cause it to happen is because of the electricity going to the brake lights. The short may be in that area.