In hindsight and after researching a little more, I think the bulk of the problem is just that I installed everything hastily and not as clean as I normally do because of the cold weather. Lots of bare metal so that should be easy. I'll then find a good solid ground behind the stereo too. I'm going to take it all apart when it warms up and splice directly inline to the Stereo switch power for a solid, and hopefully clean power source. I do have them tied to the same power source, but it's not the most solid connection. I use the XM in my OB too with the Aux In and hear nothing, so I don't think that is the problem. That is why I am not sure if a ground loop isolator would help. Right now I have it hooked to my XM and I hear the whine before the XM loads and starts feeding it audio. The noise comes on when the FM modulator is on, regardless of the input source. Not the most secure, but again, it was cold and it was easy. Right now I just have the wires shoved into the rear of the plug on the outlet. Just looking for some knowledge on which to use and why. For $12 I could just put both in, and I still might. I know FM modulators are not ideal, but I am sure I can do something to remove the hiss I am hearing.

Would the stereo be better? I intend of finding a good, close body ground.Ģnd how can I diagnose whether a Ground Loop or Nois Surpressor is needed? I am fairly certain that, as of now, the noise is there even when I unplug the audio cable. I'd rather not run an independant power wire. I was looking for a few pointers.ġst what is the best place to pull power? I want switched power, so I am still considering hooking + to the cig lighter. ONce warmer weather comes I'm going to take it all out and reinstall it. It was cold and I just wanted it done, so that was easy and accesible. I tapped into the power and ground from the acessory plug.

I am in the process of diagnosing the cause and wanted some help.Īt first I was thinking a Ground Loop Isolotor might solve the problem but the more I read, I think part of the problem is from how I wired it in. I recently installed an FM Modulator in my '06 Forester and I have been getting a bad whine from it.

Ground Loop Isolator Install Car