i'm really confused. you had a thumping that you determined was coming from the amp. then you hooked up the amp at home and it was no longer there. did you try hooking it back up in the car? if you isolated the thumping at the amp then your stereo is fine. if you didnt get the thumping when you hooked it up at home then most likely your amp is fine too. i'm confused here. maybe i'm just reading this wrong.