When my car is running, and my HU is on pause, I get this high pitch sound through my speakers. its there when a CD is playing to, but high volumes cover it up. Anywanyz, im trying to figure out how to fix it. Someone suggested to me to check the grounds. SO I did, and found that my battery terminal (-) was loose. After secureing it, I thought it had been fixed, but the next time I went out to my car, it did the same thing. This only happens when my car is running, not when im on ACC. If it was still a ground problem, I would hear it when im on ACC too, wouldnt I? Also, my lights, and my HU backlight dim slightly and brighten, all in a very fast movement. I have upgraded to big 3 with 1/0 guage, all except the alt + to bat +, cuz it wasnt staying on, so I took that one off for now, until I get a new alt. What the heck can I do to fix my noise problem?

Thanks

have you checked all of the grounds of the amp(s) and HU?

maybe try grounding them to a different spot and make sure there is a good connection

Definatly check the Head Units ground. They are weak in the stock location for aftermarket units. If that doesnt help try making a commin ground out of your equipment. Lastly if that doesnt work test out another set of RCAs to see if that is what your problem is. Only suggestions I can think of.

I dont really think it's my RCA's, got the highest grade 4-channel ones from knuconcepts.com. One of these days when I get some time I will go make double sure of all my ground connections. Thanks for the suggestions.

did you run your RCA's near your power wire? if so----it could be interfering with the signal.

hell even with my equipment i had noise----try getting a noise gate(helped me)

it could also be the internal noise of the amp if it is cheaply made

did you run your RCA's near your  power wire? if so----it could be interfering with the signal.

<{POST_SNAPBACK}>

i thot that was only a myth

it is.

The problem here is the Pioneer HU.

The problem was, again, my ground connection at the battery terminal. It was lose again, I dont know how that got by me. Damn battery teminal.

oh well, glad its fixed and just remember to check that first the next time

it is.

The problem here is the Pioneer HU.

I've never been a real fan of Pioneer, and with all the trouble I've seen their RCA connections causing, they just further my hatred.

that is kind of weird since I am not running RCA's to the rear from the HU.

are your amps/crossovers screwed on the back of ur rear seats or something metal on ur car? if so try taking them off and testing it. this problem comes from multiple ground points, it creates a ground loop and it only happens when your alternator is feeding the power to your amps because its not excatly clean power.

and it only happens when your alternator is feeding the power to your amps because its not excatly clean power.

That's an interesting statement.

The only time your alternator isn't feeding power to your amplifiers is when the car is shut off.

dammit, i meant to say isn't