Hi,

I have the following installed in my 2000 Nissan Maxima:

Rockford RFX9420
Rockford 8004 AMP
3 8 JL Subs
RFX 8810 CD Changer
I have an Audio cable running from the 9420 aux1 for my ipod.

My problem is I have a whining noise coming from the right speaker when I driving with the Air Conditioner or I have my head lights on. It goes up when accelerating or down when decelarating. The place that installed Rockford 8004 AMP, Qty 3 8 inch JL Subs also rewired ********** when they installed them. It's not as bad as it was before I had an Rockford 400.4 installed but it's annoying.

I took it to another place and they checked ********** but could not resolve it. They did the basic troubleshooting that you would do to troubleshoot this problem. They also tried a noise suppresor but it didn't help. They said the wiring was done correctly. They thought it was the amp. The other company that did the install told me it was the radio. Well, I took it to the place that did the original install. They put a Rockford DVD1 in and it did not do the whining noise. They told me it was because the Rockford 9420 uses an 8 pre out (hopefully that makes sense) compare to the DVD 1 was lower. Is there a resolution to this or do I have to go to a lower end radio to resolve this issue. Any information you have would be helpful.

 

i suspect a bad ground somewhere if the noise is proportional to engine speed. check all the grounds. make sure it's making good contact with the body of the car.

 

Did they try switching the outputs of the HU and then from the amp to determine if it is one certain cahnnel that is causing the problem. If you only have the whine coming out of one channel then I suspect it is either the output of the amp or the signal it is gettign from the HU

 

Unfortunately, I don't know much about car audio setups. I do know that the place I took it to did check the grounds and he said that they were setup correctly. They did check the connections from the amp and ran better quality wires to see if that would solve the issue but it didn't. I believe they did try swithcing the outputs of the hu.

 

I also emailed Rockford's tech support. Here is there response listed below:

Subject
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RFX 9420


Discussion Thread
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Response (Kevin) - 07/09/2004 02:36 PM

Thank you for your inquiry with us. Its not the deck causing this Because of the less voltage your amplifiers wont be producing as much output so your sound is still there its just lower. This can also be done by turning the gains down on the amplifier and keeping your 9420 on it. You may want to remove the rca's out of the amplifier and see if you still have this problem and let us know so we can figure out where to look.


I tried what they asked. I did turn the front gain down but it still did it. I disconnected the rear input but it did the same thing. When I disconnected the front input I didn't hear any music out of the speakers. If I disconnected one at a time it only made the sound on the front right speaker as I mentioned in the post. I hope this helps.

 

try switching your front input with your rear inputs and see if the problem moves to the rear. If it does, HU problem. If it doesn't...might be an internal problem in the amp