So my subwoofers will hit mysteriously and lighten up or hit really fast and hard when no music is playing. It sounds like feedback to me but i maybe mistaken. I'm trying to eliminate this. I don't know what it is an how to solve it? This only happens when I turn my headunit on and have either tuner or aux on with the mp3 player going, i could have it on 0 to max for sound level and still does the same thing. I already have a big enough ground, also i have power and rca cables running on opposite sides of the car.

 

Check the back of your head unit, something could be contacting your rca connections.

 

I agree. It sounds like interference somewhere. Just curious, what kind of amp?

 

well,

this could be a great answer, some decks come well put together

if it is a sony deck it is know to happen when you flip your ignition on it sends "AC ripple" through rca witch confuses the signal. alternators do not convert all AC current to DC and your car battery can only filter out so much if there is nothing touching your rca's then it is the deck or the amp, the amp can be affected in the same way.

i recommend getting a new deck

i think you could possibly test this with a dmm on ac or ohm's?

 

Have you checked your all your grounds? Check your grounds with an ohm meter go from any solid metal point on the car to the ground in the amp. This will tell you if you have a good conection to ground. Unplug your rca does it still do it? if so your amp is bad. If not then you have rca grounding issues is it a pioneer? You should try grounding your rca cables to the frame of your deck. check this website see if this helps you http://caraudio.com/forum/wiring-ele...-take-two.html. good luck.

 

is it just when you start the car? cuz i know some of my friends do this when they start their car but it is the rush of power to the system its self

 

is ur HU a pioneer by any chance?