It'* possible it got pushed in from constant use.

Darn.... hopefully it will still work and the gain control is stuck on a reasonable setting. Think I'll go to bestbuy and purchase that line out converter if they have it and just try it.

This amp has both low and high level inputs. This means you can use RCA cords or speaker wire. It also looks like the low level input used a small pin plug. If you do not have this plug you can purchase an aftermarket one from almost anywhere that sells car/audio and connect it to the head unit. Ill ask my buddy who works at Metra Elect about the GM radio adapter plug, but it seems any parts yard might be agood source for the harness.