Ground loop or noise filter?

[Pugsly]

after i installed m Sirius Sportster hardwired into the Aux port with the PIE amp, I now get a wizzing sound through the speackers that increases with RPM.

I am confused, do i need a noise filter or a ground loop isolator (does the ground loop get installed between the sportster and the PIE amp or between the PIe amp and where i spliced into the aux wires?)

where would the noise filter be installed? (i powered the pie amp with a piggyback fuse jumper thingy and the sportster is wired into the pass power socket behind the dash)

[virus]

I installed a ground loop isolator and to be honest, it only decreased this noise a little. I'm going to have to try to find where the engine noise is coming from.

[smoketitan]

where did you ground the PIE to?? I bet thats the issue.

try using the bracket behind the stereo that has two holes in it

and if that doesnt do the trick, just redo the lizards ground fix under the hood,and all whines will go away

[Pugsly]

the ground mod was done 3 weeks ago before the sportster install and the pie amp is grounded to the HU mounting screw.

[lizardking]

The ground fix I did was 1/0 gauge wire from the battery to chassis and chassis to engine. Two seperate grounds, this cleared up any noise I had. Your clearly getting Alt noise feedback if it raises and lowers with RPM's...