I have now been trying to find this noise for about a year and I can't seem to find a solid answer. When I am sitting in idle or will any other time really I can hear my fan click on through my stereo I also get a loud thunking noise from my RCA jacks when I unplug them or plug them in. I've been told a ground loop I've I've got three amps all of which are individually grounded to something on the car the chassis I just did all that and the noise is still there I don't know what else to do somebody says get a filter while I want to know what the problem is though there's a reason it's clicking like when I hear the fan kick on I can hear it tick.. sometimes I'll hear my turn signal like just click on it won't I don't hear it continuously but that's sometimes can anybody please help me it's driving me insane.