Sound problem
 

I had just put in a new kentwood deck with two sony explode 240W speakers in the front and two sony explode 400W speakers in the back. and after Non-Quality auto sound put my first deck in and messed it up. I put in the new one and any time i listen to my music loud for about 30 to 45 min. the sound starts to get staticey and more quieter then it was and i have gone through 2 decks thinking its an internal amp being burnt out but it does it with a brand new one so i dont really know what the problem is, so if anyone has an idea i will be glad to hear it.

Thanks