So I finished installing my aftermarket stereo today along with the gmos-lan-04. When I started up my car I heard a really annoying whine coming out the speakers. I've tried different grounds for the headunit. The weird thing is no sound comes from the speakers unless the rcas from the amp are plugged in. Also when the RCAs from the gmos-lan-04 are plugged into the sw output it plays but still continues to whine. Is this a setting in my stereo? Bad ground? Bad RCAs?

 

Sounds like the metal bracket from hell claims another one.

When you put your new HU in was it a tight fit?
Did you have to use some force to get it all the way back there?

I had a similar problem, it was because my RCA's were getting pinched in the back between the plactic wall and the HU, the force was bending them.
Do your RCA's plug right into the back of the HU, or are they a dongle that hangs off the HU.

BTW- How are them chimes/signals treating you know with the GMOS LAN 04 in?
Oh yeah welcome to the forum

 

If all else fails to fix your problem its more than likely a ground loop problem.......run the ground for your deck to the back of the car and ground it to the same place as your amps are grounded to.......and the fm antenna sometimes causes ground issues........i have done this in all my vehicles and it has fixed speaker whine everytime.......good luck.....Later

 

x2 run the HU ground to the amps and dont use the one from the harness. 18g remote wire works awesome for this

 

I know this was a mistake on my part, but would not installing the antenna adapter cause whine? I mean doesn't it serve as a ground for most headunits?

 

Not installing the antenna would be a good thing in this case........that is a source of alternator whine if it IS connected so that is not your problem.......ground the HU to the same place as the amps and you should be fine........Later

 

nope. only if u have a shitty ground would it ground thru the antenna and thats really no good in the first place. Only shitty nissans do that kind of nonsense

 

So I figured I could resolve the speaker whine by buying a ground loop isolator. It got rid of the whine however I can't hear my subs anymore. It seemed to have weakened the signal to the sub. I have my amp gain/bass boost set higher than normal and all the settings on my stereo set higher than normal. Still very little sound from the subs. Buying an aftermarket stereo is such a hassle. Does anyone else have gmos lan 04 and experience this or is it just my set up?

 

On your isolator does it have two wires that come off of it that dont go to anything? I yes than you need to ground those to the same place as the headunit and the amp. if you dont you will get a echo thru the rcas.

 

wait... lets get a bit more specific.

What speakers was the whine originally in? how many preouts does your HU have and which ones did you put the ground loop isolator(s) on?

 

The whine was coming from the front and rear speakers. The stereo has 3 preouts, 1 for the sub, 2 for fronts and rears. I put the ground loop isolator on the rcas connecting the amp to the stereo.

 

so you only have the ground loop on the front and rear preouts right? only 2

 

Man I feel your pain. Same exact problem with mine. Plug the RCA's to the AVIC D3 and its whines like crazy. Unplug them and its crystal clear. I ran grounds every damn where and still it whines. I've just given up and I decided to sell my amp and sub.

 

^^^ are the rcas ran on the left or the right side? Also running a ground so the HU is grounded to the amps instead of how it is normally will solve alot of those issues

 

I ran the RCA's down the left side 1st and had noise, so moved them to the right and still had it. So I pulled them out and just stretched them across the car right down the middle and still nasty noise. I grounded the radio straight to the Chassis, and that didn't help. I guess I could try grounding the radio to the amp.

 

ya run an 18g+ directly from the HU to the amp with nothing else. Some amps/hu's will pick up the slightest difference in ground.

Getting better RCAs might also help

 

I'll try running a ground. The RCA's should be ok. They are Rockford Fosgate, never can tell though I guess.

 

as long as they aren't fractured then your good.... i wasnt sure if maybe you had some crap rcas (tend to pick up more noise)

 

Yes, I only get whine from the front and the rear speakers. I can't hear noise from the sub. I think the next thing I'll try is grounding to the amp.

 

but there less output on the sub? I'm almost going to say the hu is going bad.... try the ground and see what happens

 

Wouldn't that be true if when the ground loop isolator was unplugged it produced the same output as it being plugged in? Once I unplug it it sounds normal but with whine. I almost think it lowers the output just to get rid of the whine. I'm going to try that ground thing and see if that works.

 

yes but you said you have 3 preouts, only have 2 ground loop isolators connected to only the front and rear.... along with less then normal sub output with a ok speaker output with the GLI connected. Either that sentance is wrong or somethings wrong with the HU. It shouldn't matter what you have connected to the front/rear the sub output should be isolated

 

I have one GLI hooked up to the rcas connecting the amp to the stereo. Sorry for the confusion. The noise is coming from the amp.

 

right... how many rcas are coming out of the stereo? and how many pairs of rcas did you run thru the car?

oh ya what HU is it? brand and model?

 

There is three outputs on the stereo. 2 are used for the gmos lan 04 and one for the sw. The HU is an Alpine 9884.