As per my other thread, I decided to rip all the wiring I have previously done out and start over from scratch. This time I ran real speaker wire to each speaker instead using most of the stock wiring and everything was soldered. Basically I did it right this time, the way it should've been done in the first place.

All the same equipment was used. Somehow, the hiss is gone even with the gains turned up higher than they ever were before. If I put my ear to a tweeter I can barely hear a hiss but it's nothing a passenger would ever notice. Also, bass response is much better. I don't know exactly what made the change but I'm glad I took the time to wire it right.

I did find many loose connections to the amps and components including the ground to the amp. I must've been in a real hurry when I installed it the first time.

So for those of you running through the stock amp, there is hope of getting rid of the hiss.

 

So you ran individual speaker wire to every speaker from the stock amp and took out all the OEM speaker wiring? If so what gauge speaker wiring did you use? Gives hope.