4.8 is whining/whistling noise

[brucemillar]

What you describe is ground loop whistle. Give it a GOOGLE you will see lots of suggestions on how to correct it. On my 4.8 it was the output transistors on the BM54 radio in the trunk.

[X5only]

Originally Posted by brucemillar

What you describe is ground loop whistle. Give it a GOOGLE you will see lots of suggestions on how to correct it. On my 4.8 it was the output transistors on the BM54 radio in the trunk.

Brilliant, thanks for the pointer Bruce! I think I know what caused it as I had recently worked on my audio system. I never used to have this noise.