I had my sirrus raido installed at a electronic store and they put it in according to Mazda insturctions. The antenna is on top of the trunk right in the middle. Now when i wash the car the trunk leaks right where the wire for the antenna is. Iam thinking a piece of tape or dab of silicone. Any ideas?

I have my antenna inside the car, just under the rear windshield and it works great. Perfect reception. I don't really see the need to put it on the outside.

Yeah, I have mine inside as well. I'd just relocate it.

I installed mine just behind the sunroof, centered on the top of the car. Run the wire thru the sunroof opening, down the front pillar, to the tuner.