I have had an alpine for the past 3 months works fine love it yesterday it begain to cut off and I did not nottice it untill I put the car in park but when I press and hold down the brake the radio cuts off but as soon as I press the gas my radio cuts offf I have check the connetions to the amp what eld could be wrong

 

does the radio turn off, of the music just kind off stops with the radio on?

 

That's quite a sentence there.

So when you hold on the brake, it cuts off, and when you press the gas, it cuts off? I'm confused. As far as cutting off goes, I'd guess it'd either be connections (including ground) or overheating.
You checked your connections to the amp? A separate amp? Or did you check the actual head unit -> factory wiring connections?

 

Also try it with your AC,headlights,wipers,etc..EVERYTHING on and even play with the windows a little bit. If this also affects it, it may be an alternator problem. Being that the radio is an accesory, and not something that is needed, it is last to draw power.If your alternator isnt working properly, the radio would be the first thing to shut down. When you press the brakes (POWER brakes), your using the power for them, and the brake lights, thus shutting down your radio. When you press the gas the alternator pulley is moving more, then charging your car.

--Don

BTW when you try turning EVERYTHING on in your car, please be in your own driveway, as we dont want to see your next post as "help Im stuck"