BA Premium sound - terrible radio reception.

[Smoke Pursuit]

Hey guys i have an 04 BA XR6 with factory premium sound and the FM radio reception is no where near as good as our Territory or BA Ute.... Its always scratchy and really isnt what it should be.

Any ideas on what could be wrong, its not an earthing problem as the it doesnt increase or decrease when you accelerate etc, but more a signal problem. Where is the FM antenna located, i know the rear window incorporates the AM, but could the FM be stuffed?

Thank you very much!