I’m having a common problem that I see other people are facing. I have 2004 Galant GTS with the stock infinity sound system. I am trying to connect subs and an amp to my car. Everything is connected but the subs are not receiving any signal from my head unit. I know that many other people have this problem and was wondering if anyone has connected their stock infinity system successfully and if so how? Please let me know. Could this be all I need http://www.autotoys.com/x/cust/product.php?productid=5448 ?