Try as I may, I cannot rid the system of the annoying ticking sound and light humming that I get. I get it while the engine is off but key is in the on position (not started though) and I attribute it to some noisy electrical components like the electric fuel pump and other pieces under the hood. When started, it's even much worse, getting the high frequency whine associated with engine RPM's. I've tried many different things. It's not audible when I use just the head unit. However, when I use a line driver to step up the signal voltage, it's certainly audible and quite annoying. I was thinking that I might want to look into an isolated dc/dc power supply to feed the head unit and line driver/dsp ...
Does this sound like something that might correct the issue?
I found this unit that David Navone produces, but it seems a bit pricey for what it is. http://davidnavone.com/product/n-ip1...-power-supply/