Car Stereos: Head Unit, sony head unit, pioneer subs

Question
Hi I have a Sony Head unit with RCA rires, power and a remote shutoff wire running to my trunk to power my 1000 watt Sony amp that runs 2-12" Pioneer subs, I also have Alpine speakers running from the same head unit but not amplified (so u get an idea). The problem is that when my engine is running I have a fast clicking sound coming through my speakers when it is in the tuner mode and aux mode but no problem in cd mode. When I turn the engine off i dont get this sound and the wires are seperated that run to the amp so i dont think thats the problem. When i speed up the engine the clicking gets faster.  Is it the RCA's maybe ?
Please Help Thanks

Answer
Hi Tyler,

A clicking sound when the car is on is definitely some sort of interference.  Why it's clicking though, I'm not sure.  ANd having the problem not be there in CD mode is especially troubling.

If you can get your hands on another head unit to test, I'd suggest starting there, as it's the source of the sound, and if it's only doing it in 2 of 3 modes, that's where I'd begin.

I'd doubt it's the RCA/amp/subwoofer combination causing your issues, as then it'd be unlikely (but not impossible) to be coming out of the car's speakers that aren't on the amp.

Look into testing with another deck (if you know someone with another sony head unit you can plug in just to test, that'd be a good start).

Disconnect the RCAs entirely, and remove the inline fuse running the external amp to eliminate it as a possibility of the source.

Check your deck's grounding aswell.  Perhaps remove it from the harness and ground it at the chassis itself so you can ensure it's a good clean ground.

Good luk,
Justin