hi all, semi noob here

have a sound problem, please any help? and if possbile can u post the amp diagram for the connection

05 pac sound + dvd changer, no woofer, i added a woofer, used high imput from one of the rear speakers
having a humming noise( humming noise is on even if the stereo is off and engine on, engine off and stereo on, no noise, engine on and stereo on still noise in backround when amp not used in the sound), if any one could help please, tried the low level imput from the system, but the sound level won't change
i guess cuze of the connection type

any help is NICE

 

where do u have your amp ground at? it is a direct to ground or just body?? need to have a really good ground or u will get feedback from other systems or engine

 

its grounded at one of the screws that hold the stock amp to the body, tried the same ground the stock amp uses behind the tailight, and tried the seat bolt

 

any one else?