it think i found your problem.you are using the wrong harness adapter labeled on pic.the way you have it wired,it is bypassing the front amp that is why there is no bass.connect A to A,and B to B.[/br]
[/br] connect the headunit harness to this in car harness.[/br]
[/br] this 8-port square connector is for the speaker wire,it goes from stereo to front amp(it appers that you dont have the harness adapter,i have the wiring instructions if you want to cut it,but it would be better if you found the adapter)[/br]
[/br] i'll check back before i go to work,if you need more onfo let me know.