I have a slight engine whine that comes through my speakers when the car is running. It isn't very loud and once my HU is above level 10 volume or so I can't even hear it. However, I just noticed it and its bugging me now, so I'm trying to make it go away. I also noticed this evening that, when my car is off, but the key is turned to accessories, that I could hear my heat a/c fan through my speakers as well. When I turned the hear off, the noise went away. I just ran a wire from the casing of the HU tonight to bare metal behind my dash, thinking that I maybe needed a better ground. That didn't change anything. I know my grounds to my amps are good and my RCAs are ran on the other side of the car than my power wire. I do have my remote start wires running beside the RCAs though. Not sure if that is enough to cause noise. I'm stumped to why I can hear my fan through my speakers. Anyone have any thoughts? Also, I'm pretty sure no wires are touching anywhere, all connections are secure and my amps arn't mounted to where they can come in contact with the chassis.