I have the same problem too, what i did was i ran the remote wire up to the front and put a switch on it so when i start the car or turn the radio off i could also turn the amp off. I used the speaker to rca converter to connect my amp because i didn't want to change the stock deck, so i think the reason why this loudly bass comes for about 2 seconds is because the amp doesn't know when to turn itself off and on because the stock deck as no remote wire and the antenna motor only gets power when the antenna goes up or down so the amp must stay on all the time.