I have a question relating to this...If you vent your parcel tray, do you get great deal of hiss, tire noise, etc. coming from the trunk? As a matter of practicality, what do you do when the sound is down? Or is the sound never down? I am going to do some audio this summer and the amount of increased noise into the cabin from the trunk may be a deal breaker for me as far as a larger Sub is concerned.