Is there a button to push for when the top is down to hear the car stereo? The volume is fine for when the top is up, but when the top is down you can barely hear the music. We can carry on a normal conversation in the car with the top down, but we can't hear the radio. we have the Kermon upgrade package. Does anyone have any ideas (center speaker in front not working, you aren't suppose to listen to music with the top down, design flaw, operator error)?