Is this a grounding issue?
I have kind of an interesting issue I'm hoping you can help with. My CarPC has some fairly loud static using onboard audio. It does not fluctuate with volume, so if I turn the music up enough I can't hear the static. I figure this is because my ground/power/audio are all basically pretty close to each other, but here's the interesting part: I unplug the audio from the motherboard and instead plug it into the zune (without moving the wires much) and the static drops to near nothing. So my thoughts are a grounding issue with the Mobo or interference from the power/ground wires affecting audio on the mobo.
Via epia m13000 (yeah, it's old)
Power, ground, audio wired to the factory harness (line-level audio into harness goes to factory amp)
Any ideas would be appreciated, as I have a few ideas but I'm not sure where to start.