Originally Posted By: tfabris
Also, I'm investigating how to get rid of the last little bit of ground loop noise, and I'm thinking of trying out an isolated power supply.

Right now I'm using one of these:
https://www.pololu.com/product/2851

And I'm thinking of switching to one of these:
https://www.digikey.com/product-detail/e...81-5-ND/2242601

What do you guys think? Would that power supply at least work in my prototype?


Looks very expensive.
Which audio output are you noting the noise on, the Home-mode RCA jacks, or the car-mode outputs: docking connector jacks? or Home-Dock jacks?

The docking-connector jacks appear to have isolated signal grounds, whereas the RCA jacks use the main earth/chassis ground. I think.