buzzing sound after switching head unit

[bcst86 5]

well i got my old alpine cda-9827 back and decided to use it in my tundra. took the factory unit out and saw there was a small external amp. after looking around i saw that i needed the Metra 70-8113 wiring harness to keep the factory amp in there. its got the rca cables for front and rear speakers. super easy to wire and install everything.

after i got everything wired up i turn the key, but dont start the truck, and it sounded great. way better than the factory unit. so i put everything back in the dash and the dash piece back in and screw it back on and listen for a bit more.

later on i need to go somewhere so i get in and start my truck and there is a buzzing sound that is constantly going. so i turn the truck off and it goes away. the buzzing only comes on when the truck is started. what would cause this and how do i stop it?

[bcst86 5]

saw something about a ground loop isolator. so i will see if any of the local car audio shops have one and will try that

[Julian 641]

Check your grounds and make sure they are grounded well. That's what typically causes buzzing/whining.

[bcst86 5]

the ground from the HU? i just have it connected to the factory harness. i guess it could be how the factory amp is grounded? i took my saz-1000d out since im not using it at the moment

[TeamNemesis_Jessie 1]

check you RCAs move the ends around and see if it stops may need new RCAs or you may just need to ground the RCAs to your HU

[bcst86 5]

the wiring harness rcas? this is what it looks like. front rca, rear rca, power, ground, power antenna, rem

Edited November 18, 2010 by bcst86

[bcst86 5]

tried a new ground location for my HU and it still buzzes. only thing i can think of is that the stock amp inside the dash may need a new ground but i cant find the ground wire on it.

sucks i may just have to deal with it?