Noise, Noise, and no Noise
Ok, so after migrating from a on-board sound card that simply did not work to a Turtle Audio USB sound card I've run into a problem.
On my bench in the house it sounded perfect. The audio was supurb.
I have a Mazda 3 with a factory aux jack. I took the acc line directly from the radio harness and I also grounded the carPC to the ground in the radio harness.
I took it out to the car, hooked it up and gave it a shot. With the engine on acc so the radio would come on I turned the carPC on and it booted. Radio sounds fine. I switch over to the "Media" (aux jack) and I hear fuzz. The engine is NOT on at this point.
Crank the car over to turn it on and when the car runs you get the alternator noise.
So, maybe a bad audio cable. Swapped it out, nope, not the cable. Plug in head phones and no noise what so ever (other than the audio of source).
I hooked up my house dvd player using a power inverter and a RCA to 3.5 standard audio jack (monster cable) and the audio is just fine, even with the inverter
So, I'm left with noise when using the Aux Jack with the carPC only. Plug anything else in to the aux jac and it works. Plug headphones into the carPC and the audio is great.
What gives? Yeah, I'm sure you're going to tell me its the ground wire or maybe even the acc wire. What give, shouldn't the radio do the same thing when I switch back to it while the carPC is on?
I did run across this site:
I'm not sure where I should supress the noise though. Any thoughts?