Audio Systems: dont know, stock radio, amp

Question
i had a system hooked up in my in a 03 impala amp and speakers in the trunk to a the stock radio it works but when i turn the volume up to a certain level the amp and speakers in the trunk stop and it plays regular

Answer
ONE: Wires to the amp are too small guage.
TWO: Battery and alternator cannot sustain the current demands of your amp.
THREE:  Shorts in the wiring to the speakers.
FOUR:  Over drive - you are turning the amp up too far and it is going into overload.

These are some of the possibilities for you to search down.

C