Hey guys...question for ya. My speakers are having a buzzing noise from them. They are polk momo mc6500. When i seem to turn the truck on or off is when the buzzing sound is real bad. Almost when the lights dim. What could be causing this? thanks

 

I'm guessing this is powering your speakers? What about Head unit? Alpine? More than likely you need to look at these first? How does the sub sound? Does that pop? Unplug your RCA's at the amp if they're accessible, does it still buzz?

Answer these questions first, you'll be leaps and bounds ahead in the troubleshooting process.

 

Is it a whirling sound? Does it get faster when you step on the gas?

If so, are the RCA lines and power lines run close together? This could be your problem. The RCA lines are picking up something from the power lines and amplifying it into the speakers.

Run the RCA lines and power lines as far away as possible. One down one side of the truck and one down the other side

Maybe this will solve the problem

 

Take a look at Bartak1's thread over here:

https://www.f150online.com/forums/sh...d.php?t=282818

There's some good troubleshooting ideas towards the middle.

 

check your ground connections.

 

Anytime your running ground and/or RCA next to your power wire is when you will have this problem. Also could be a bad ground..If none of these are your problems, you might want to relocate your ground.