So almost every morning when I get in my truck to go to work, and I turn my truck on my left tweeter will have a light buzzing noise when I turn the headunit on. when the cars off and the units on it wont buzz, and sometimes when I restart my car or turn my unit off and on ill hear a pop like sound and itll stop. Sometimes coming back after a while but for the most part not.

 

Do you have a amp hooked up in your truck?

 

if you do have a amp in your truck,it could be picking up interference through the rca cables,Make sure they are shielded and they are away from the power wire,Check your grounds and if you have the radio ground connected to your harness behind your radio,that also can sometimes pick up interference,i would just ground it to metal...the popping sound can also be from your amp if you have one,you will need a ground loop filter,that will stop it.....i had the same problems that you are having right now,thats what i had to do............anyone else out there please let write and see if i missed anything........i know it can be a pain!!

 

Do you have the stock HU or an aftermarket one?

 

I would suggest NOT running power and audio along the same route. It's a bit more hassle, but I run my power and remote up the driver side, and I run audio up the passenger side.

Also check to make sure you did not cross wires. Meaning make sure positive isn't in negative, etc etc. Like the above posters said, use shielded cables. The tweeter noise is definitely interference, and perhaps a bad ground on the amp.

 

Aftermarket, took it out jiggled some wires and it hasnt done it since, thanks for the help boys.