I bought an MP3 kit to plug into the back of my radio so my car could play MP3s from a MP3 player or (with another adapter) through Bluetooth.

Anyway, I got it rigged up and it works but it has this high pitched noise it makes most of the time and that gets worse when you accelerate.

The vehicle does not make this noise when using the regular radio or CD player.

Will better plug wires fix this or would bad wires also effect the radio and CD player.

Does anyone know of a fix if it is not the plug wires?

 

Is the sound there with only the kit installed and no mp3 player or Bluetooth adapter plugged in?

 

The sound only happens when the player is set to AUX. So it happens whether music is playing or not.
So yes, it is always plugged in but only makes the noise when AUX is selected.

Thanks for joining in. I need the advice.