Hi guys.

Firstly, I self installed the aux / 4 ch output from Phreddy into my HU, so any issues I'm having are self inflicted! Don't want to sully Phreddy's good name.

Basically I have a grounding issue, which wasn't always there. I've pulled the dash apart so many times I've probably done something to cause this.

When I listen to the CD/radio through the amp, no engine whine. I have a good clean sound. With the ipod, there has been a small engine wine, particularly when power is plugged into the ipod. But i could live with it if the volume was up enough.

Now the aux circuit doesn't activate when i press the button, unless the power plug for the ipod is plugged into the cigarette socket. Take it out, and the circuit breaks, so i guess its earthing through the power socket via the ipod. However, if i take out the power plug, and ground the earth wire from the aux switch, it works again, but with a little bit of whine.

My question is, should i just ground the switch 'locally' underneath the centre console. Or is the ground from the switch most likely loose inside the HU? Would I be better trying to ground the switch inside the HU. Just trying to avoid dismantling the HU again, but will do if this is most likely the culprit and the 'fix' would eliminate the engine whine.

Thanks for your time